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| Subject | Date Asked |
| Calculating Random Numbers | 2/8/2012 |
| Q: I have been wanting to create a computer program that produces random numbers based on various ... A: The term 'mod' is used in mathematics to mean the remainder after division. ... | |
| Calculating Random Numbers | 2/6/2012 |
| Q: I have been wanting to create a computer program that produces random numbers based on various ... A: If the number were desired to be between 1 and 26, don't multiply by 26, just take mod 26 and add 1. ... | |
| Calculating Random Numbers | 2/5/2012 |
| Q: I have been wanting to create a computer program that produces random numbers based on various ... A: A true place for generating random numbers can be found at http://www.random.org/ To generate a ... | |
| LP | 1/31/2012 |
| Q: Solve the following L P problem through SIMPLEX method Maximize Z = 5x1 + 6x2 Subject to 2x1 + ... A: I'll attach it in a file. The 1st column is the value of the variables for each equation. The 2nd ... | |
| LP | 1/31/2012 |
| Q: Solve the following L P problem through SIMPLEX method Maximize Z = 5x1 + 6x2 Subject to 2x1 + ... A: The variable to add first on a straight forward SIMPLEX problem like this is the variable with the ... | |
| mathematics | 1/26/2012 |
| Q: explain the word depreciation A: Depreciation is a loss of value. A definition is found in ... | |
| Homework help | 1/25/2012 |
| Q: solve sec^2(x)=1 over the interval [-pi/2,5pi/2] can you please go step by step because its been ... A: It is known that sex(x) = 1/cos(x). If sex^2(x) = 1, then sec(x) = 1 or sec(x) = -1. Since cos(x) ... | |
| math | 1/24/2012 |
| Q: Find the smallest positive integer whose product after multiplication by 543 ends in 2009 A: Trying to solve 543n mod 10000 = 2009? In a spreadsheet, I put 543 in A1, 3 in B1, =B1+1 in C1, and ... | |
| math | 1/23/2012 |
| Q: Lynn is walking from town A to town B, and Mark is riding a bike from town B to town A along the ... A: The two equations at the 1st meeting are X + Y = d, where d is the distance between towns. Since 40 ... | |
| Proving Pythagorus' theorum using trigonometry | 1/23/2012 |
| Q: In my senior year at school, our maths teacher taught us how to prove Pythagorus' theorum using ... A: It is known that sin²(x) + cos²(x) = 1. It is also known that if the sides of a right triangle are ... | |
| Proving Pythagorus' theorum using trigonometry | 1/20/2012 |
| Q: In my senior year at school, our maths teacher taught us how to prove Pythagorus' theorum using ... A: Ways to prove it are found in http://www.mathsisfun.com/pythagoras.html Open it up and page down to ... | |
| modules of a function | 1/20/2012 |
| Q: what values of x satisfy the equation |3x| = 2x + 5 A: This problem generates two problems to look at. They are 3x = 2x + 5 is x is non-negative and -3x = ... | |
| Trignometry / Pre Calculas | 1/19/2012 |
| Q: Convert 2.5 radians to degrees. Give the answer to the nearest ten minutes or tenth of a degree. A: It is known that 180° is the same as pi radias. Therefore to convert radians to degrees, multiply ... | |
| modulus function | 1/18/2012 |
| Q: Solve 1 + |2x-3| = 3x A: This could be changed by subtracting 1 from both sides into |2x-3| = 3x - 1. To solve, we would ... | |
| Can you please help me with this word problem | 1/15/2012 |
| Q: Given the length and width (in feet and inches) of a rectangular room and the price per square yard ... A: 1. length of the room, width of the room 2. square feet of the room, which can be converted to ... | |
| simple equation | 1/15/2012 |
| Q: sir how can we solve these equations? X^2+Y^3=5274 Y^2+X^3=7148 A: In a spreadsheet, use A1 as X and B1 as Y. In cell C1, put =5274-A1^2. In D1, put =7148-A1^3. In E1, ... | |
| Rate Tables | 1/5/2012 |
| Q: An ostrich can run at a rate of 50 miles in 60 minutes. At this rate, how long would it take an ... A: Since it is known that distance = rate * time, which is written as d = rt, we know d = 50 and t = ... | |
| Algebra coin word problem | 1/4/2012 |
| Q: A parking meter accepts nickels, dimes, and quarters, there are 32 coins inside with a total value ... A: Assuming that Grady has something to do with the parking meter ... If all of the coins were ... | |
| Sequence and divisibility | 12/24/2011 |
| Q: The first term of an arithmetic sequence is 3p+5, where p is a positive integer. The last term is ... A: The terms go from 3p+5 to 17p+17, and they are by 2, so take the last term minus the first term, ... | |
| how to prove a rule of nth powers | 12/21/2011 |
| Q: How does one prove that if the index is "nth", and under radicand is "a" to the nth power that this ... A: I'm not sure I understand what is being asked, so let me state it in my words. The radicand is the ... | |
| Math Proofs | 12/20/2011 |
| Q: Let A, B be sets. Prove: A - B= A intersection B if and only if A = empty set. A: Since A - B would be the set with elements that are in A but not in B, and A intersect B would be ... | |
| math | 12/19/2011 |
| Q: 13.0693 rounded to the nearest hundredth A: The number 1 is in the ten's position, the number 3 is in the one's position, the number 0 is in the ... | |
| Math | 11/29/2011 |
| Q: I need to find the rate of this table. The numbers are X:-4, 1, 5 Y:-3, 1, 4 Thanks A: The rate would appear to be x goes from -4 to 1 by adding 5, and from 1 to 5 by adding 4. For y, we ... | |
| philosophy of numbers | 11/29/2011 |
| Q: I am not a math major or student but I am very interested in math in general. Numbers are an ... A: I can't say why, but that's why I'm a math major. Math rules all make sense and they never change. ... | |
| Probability discrete math | 11/28/2011 |
| Q: How do you solve this question? i got the answer for it on the link but i'm not sure how you get ... A: I don't find that address. I will assume we have n couples. The number of ways to seat the men is ... | |
| Maths Application Example ? | 11/28/2011 |
| Q: The Above Attached Example of Children becomes which Maths application ? Multiplication Probability ... A: There is no e-mail address in this message, so I will type it out in the message for 3, 4, and 5 ... | |
| Dividing a circle into 45 equal segments | 11/26/2011 |
| Q: I wish to make a circular board with a diameter of 350mm and then divide this into 45 equal ... A: Since the diameter is suppose to be 350mm, the radius is 350/(2pi). This would make the radius ... | |
| Maths Application Example ? | 11/25/2011 |
| Q: The Above Attached Example of Children becomes which Maths application ? Multiplication Probability ... A: I have attached a file with the total number of ways of getting each case. The 1st column is the ... | |
| Trigonometry | 11/22/2011 |
| Q: Evaluate 5i^-15 - 3i^9 + 2i^-19 A: To do this, first we convert the numbers from a + bi to c*sinA + d*cosA. Since i is where A = ... | |
| Equation? | 11/21/2011 |
| Q: I’m looking to figure out an equation that can forecast sales. For example let’s say I have sales ... A: The best way to do it is to plot the graph and see if it looks linear or parabolic. However it is, ... | |
| Precalculus Functions | 11/19/2011 |
| Q: I'm really stumped on this question. Any help in isolating the equation would be really helpful. ... A: 30 cm is at rest; stretched down to 38; stretch is reduced b 3/4 each time it bounces. That sounds ... | |
| Algebraic inequality | 11/18/2011 |
| Q: Given that a > 0, b > 0, and c > 0, prove that a + b + c > 3abc implies a^2 + b^2 + c^2 > 3abc. A: This statement is false. If a = b = c = 1, this means that a² = b² = c² = 1, so a+b+c = 3, ... | |
| Equation? | 11/17/2011 |
| Q: I’m looking to figure out an equation that can forecast sales. For example let’s say I have sales ... A: Do linear regression on the data 1 25,000 2 30,000 3 28,000 4 27,000 5 30,000 There are 5 points, ... | |
| trigonometric identities | 11/17/2011 |
| Q: Can you help me with this task? cos(x+y)=1/5, cos(x-y)=1/5 ; tgx * tgy=? Please and thank you! A: I'm not sure what tgx or tgy mean. An answer to this question would be to say y=0 and cos(x)=1/5, ... | |
| expected value | 11/13/2011 |
| Q: I was having a discussion with a friend, who like me, is an engineer, so we have pretty good ... A: The way to do this would be to count the number of possibilities. On the first one, if three cards ... | |
| Discrete Math | 11/13/2011 |
| Q: I have one problem and want your help. "If there be given nine lattice points ( point with ... A: I'm not sure I fully understand the problem, since I don't recall the meaning of "lattice point". It ... | |
| How to solve simple equations? | 11/8/2011 |
| Q: I'm currently having difficulty understanding the following examples of equations. 1. Solve/find x ... A: To solve equations, first put the x terms on one side of the equation by addition or subtraction, ... | |
| Pipe and money problem | 11/6/2011 |
| Q: 1) A large pipe and a small pipe are used to fill a tank and a third pipe is used to drain the tank. ... A: 1) Let's say the tank takes 36 globs of liquid (who knows how much a glob is, but each glob is the ... | |
| ms 8 answers | 11/5/2011 |
| Q: 4. Strength tests carried out on samples of two yarns spun to the same count gave the following ... A: To get the overall effect, with the number N, mean M, and variance V, compute the total variance. ... | |
| Trigonometry | 11/4/2011 |
| Q: Can you show me how to solve this problem using the inverse trig functions and reference angles ? ... A: The inverse sin is also known as the arcsin. Using that, it is known that 2x = arcsin(-0.7635). From ... | |
| Maths -Circular permutation | 11/2/2011 |
| Q: 1)Why for circular permutation atleast 3 distinct objects are required. 2)Will any arrangment of two ... A: Lets call the people A, B, C, D, E, F, ... Start with person A and ask him to sit down. Since we ... | |
| Maths -Circular permutation | 10/31/2011 |
| Q: 1)Why for circular permutation atleast 3 distinct objects are required. 2)Will any arrangment of two ... A: To think of in geometry, it takes three non-liner points to define a circle. If we only have two ... | |
| Maths-Permutation | 10/22/2011 |
| Q: In how many ways can 5 letters be posted in 3 post boxes, if any number of letters can be posted in ... A: The answer is P(5,3) if the order of the boxes is not worried about; that is, 5!/(3!2!) = 120/(6*2) ... | |
| solutions | 10/19/2011 |
| Q: 1. A bank has a test designed to establish the credit rating of a loan applicant. Of the persons, ... A: 1. At the end of the problem, it states that only 4% of the people will fail, which mean 96% will ... | |
| Stats | 10/12/2011 |
| Q: I'm one of the few fans of the CFL and had been reviewing the following statistics: In 2005, there ... A: The 1st equation comes out right, but the 166 is really 162. Note that, as you said, there were 81 ... | |
| Quantitative analysis for managerial applications | 10/9/2011 |
| Q: i need answer for the following questions 1. A bank has a test designed to establish the credit ... A: 1. Pass 0.95 0.05 No Pass 0.10 0.90 Let the chance of passing be P and the changce of ... | |
| Logarithms | 10/8/2011 |
| Q: I am having trouble with answering this logarithmProve that: log(5/36)-log(5/9)=-log4 I know that ... A: Given the equation log(5/36)-log(5/9)=-log4, as you have said, this can be rewritten as log(5) - ... | |
| Interpretation of Graph - | 9/27/2011 |
| Q: I was reviewing the two charts = figure 1 and 2 for the following article, specifically figure 2: ... A: The first chart divides up the raitos for men and women. It looks like most of the men have a 97% ... | |
| Chess Indoor Game - Reinventing - Maths Application. | 9/27/2011 |
| Q: Re engineered Chess Board Layout. where the Total Number of squares will be 144 i.e. 12 square ... A: This looks like a game that would be of great interest. I like the new piece, the jack. I can say ... | |
| Chess Indoor Game - Reinventing - Maths Application. | 9/27/2011 |
| Q: Re engineered Chess Board Layout. where the Total Number of squares will be 144 i.e. 12 square ... A: Yes, this is true that is the board has an odd number of squares in both directions, there is a ... | |
| Interpretation of Graph - | 9/27/2011 |
| Q: I was reviewing the two charts = figure 1 and 2 for the following article, specifically figure 2: ... A: Note that the two curves drawn add to 100% all of the way across. The x-axis is the ratio of the ... | |
| Chess Indoor Game - Reinventing - Maths Application. | 9/26/2011 |
| Q: Re engineered Chess Board Layout. where the Total Number of squares will be 144 i.e. 12 square ... A: This sounds like a whole new game that would be fun to play. For example, the bishops could guard ... | |
| maths | 9/25/2011 |
| Q: strength tests carried out on samples of two yarns spun count gave the following results: ... A: No, it doesn't, since A and B are closer than the variance say is really small. For the first one, ... | |
| determinants | 9/23/2011 |
| Q: question is in the image A: Since the lower part of the matrix is 0's, the determinant is the product of the diagonal elements. ... | |
| quantitative maths | 9/22/2011 |
| Q: Q1- A bank has a test designed to establish d credit rating of a loan applicant. Of d persns, who ... A: Q1: Of the people who default, 90% fail the test. Of the people who will repay, 5% fail the test. ... | |
| graphing question | 9/20/2011 |
| Q: I need to know if there is a function which describes the series below The series is defined that ... A: The way to find the answer is to solve the equation k(k+1)/2 <= n for the greatest possible k. Once ... | |
| graphing question | 9/18/2011 |
| Q: I need to know if there is a function which describes the series below The series is defined that ... A: The sum of 1 to n is n(n+1)/2. To show this be examples, if n=1, n(n+1)/2 = 1*2/2 = 1; if n=2, ... | |
| graphing question | 9/18/2011 |
| Q: I need to know if there is a function which describes the series below The series is defined that ... A: Note that in the series, there are 2-2's, 3-3's, 4-4's, etc. This would make the pay the sum of ... | |
| Well Known Statistical Computer Programs/Applications | 9/17/2011 |
| Q: http://en.wikipedia.org/wiki/Statistics Which are the well known Statistical Computer ... A: A list of the major languages that are used is found in ... | |
| Branch of Mathematics - Statistics - Application in Sports | 9/16/2011 |
| Q: Statistics - Applications in Sports. We see so many Sports Statisticians who have a Statistical ... A: The statistics for each player or team is kept on the computer somewhere. The reporters just have ... | |
| Graphs | 9/14/2011 |
| Q: Greetings, I am studying graphs created from data generated from natural phenomena. I am looking ... A: Using linear regression, the best fit straight line can be found. When the error in the ... | |
| Proportional reasoning (2 QUESTIONS) | 9/14/2011 |
| Q: 1. The average undergraduate tuition for full time (in state) students at 4-year institutions ... A: 1. If it increased by 9.3%, it is at 109.3% of what it was. If we take $7570/1.093, that gives us ... | |
| problem sets | 9/14/2011 |
| Q: LaDonna has a banana. She eats 3/5 of it and then gives the rest to her younger brother, Hector. ... A: After LaDonna has the banana, there is only 2/5 of the banana left. Hector eats 3/5 of this of the ... | |
| Graphs | 9/13/2011 |
| Q: Greetings, I am studying graphs created from data generated from natural phenomena. I am looking ... A: The best method would be to take a piece of graph paper and plot the point. For example, if we had ... | |
| trigonometry | 9/11/2011 |
| Q: the sum of two consecutive positive integers is subtracted from their product to obtain a difference ... A: The 1st number is n, so the 2nd number is n+1. The sum of the two is 2n + 1 and the product is ... | |
| trigonometry | 9/11/2011 |
| Q: The sum of the lengths of the two perpendicular sides of a right triangle is 30 cm. What are their ... A: The square of the length of the hypotenuse is the sum of the squares of the sides. For this to be a ... | |
| Are These Correct? | 9/8/2011 |
| Q: If it isn't too much trouble, would you mind checking to see if my answers are correct for these ... A: The questions that have been answered all look right. For the last question, it would be 3. To be ... | |
| Decimal Points Number Raised Power to Decimal Points Number | 9/4/2011 |
| Q: Some examples of Power / Exponent / Index 1. 2 raised to 3 2 ×2 ×2 = 8 2. 1.1 raised to 1.1 ... A: The problems with an integer exponent were done correctly. However, if we have a^b and b is not an ... | |
| geometry | 9/2/2011 |
| Q: First angle of a triangle is 18 less than double the second angle. the third angle is 10 more than ... A: Let that angles in a triangle be A, B, and C. It is known that A + B + C = 180 degrees. THe ... | |
| Determinant | 9/2/2011 |
| Q: Without expanding(i.e using properties of determinant ) show that the value of the determinant is ... A: Take (1, 1, 1) by a, b, and then c, giving (a, a, a), (b, b, b), and (c, c, c). Add these together ... | |
| REPLY TO YOUR EMAIL | 9/1/2011 |
| Q: I got a response saying you couldn't locate the question I linked to my email: I went ahead and ... A: I'm not sure if I answered this question, but will respond to it. Since x goes from 1 to 5 and then ... | |
| Correct Answers? | 9/1/2011 |
| Q: Would you mind checking to see if my answers are correct to these problems? Thank you so much. ... A: Problem 3 was: A community 5K run will award $50 to the winner. 65 people enter the race, and they ... | |
| Complex number | 8/31/2011 |
| Q: Represent following complex numbers Z1=1+2i and Z2=5-7i by points in Argand diagram and hence ... A: The Argand Diagram is found in http://mathworld.wolfram.com/ArgandDiagram.html . It is a normal x-y ... | |
| Writing New Mathematical Equations and Theorems | 8/2/2011 |
| Q: Writing New Mathematical Equations and Theorems ----------------------------------------------- ... A: The best way I've found to find something new is to keep reviewing old problems. For example, it is ... | |
| Maths-Trignometry | 8/2/2011 |
| Q: [Sin^3(pi+x)/cos^2(pi/2+x)]*[sec^2(pi-x)/sin(pi-x)]* [tan(2pi-x)/cosec^2x]=tan^3x A: The problem: [Sin^3(pi+x)/cos^2(pi/2+x)]*[sec^2(pi-x)/sin(pi-x)]*[tan(2pi-x)/cosec^2x] = tan^3x. ... | |
| Math | 7/29/2011 |
| Q: Prove that 1+1=3 A: The proof of this has a flaw in it, but looks good at first. There are many ways to do it. Let y = ... | |
| math | 7/29/2011 |
| Q: a spider climbs on vertical wall. in one minute he jumbs 2cm up and slips 1cm down.then how much ... A: For the first 7 minutes, he climbs 2 and slips down 1, which is an overall effect of +1. This means ... | |
| Maths-Trignometry | 7/28/2011 |
| Q: If 2sin(x+pi/3)=cos(x-pi/6) then tanx+sq.root(3)=0 A: It is known that sin(a+b) = sin(a)cos(b) + sin(b)cos(a) and cos(a+b) = cos(a)cos(b) - sin(a)sin(b). ... | |
| Max./Min. Word Problems | 7/27/2011 |
| Q: QUESTION 1: A can (right circular cylinder) is to be made to hold 1,000 cm^3 of oil. Find the ... A: 1) The volume of a cylinder is equation [1], V = pi*r^2*h where r is the radius and h is the height. ... | |
| Reflective Character Series - (Exact Replica of the Character/Letter/Alphabet in Mirror) | 7/27/2011 |
| Q: As similar to Reflective Number Series. we can also note down the Reflective character series for ... A: 1. For lower case letters, the refelctive ones are i, l, m, n, o, t, u, v, w, x, and z if the l is ... | |
| Mirrored Numbers - (Exact Replica of the Number) - Optics & Real Life Use ? | 7/26/2011 |
| Q: What i observe by looking at the Numeric Whole Numbers(Integers) in Mirror (Glass) Object are the ... A: You up at what time? It's 3 in the morning where I am ... The only usefullness I see about ... | |
| Mirrored Numbers - (Exact Replica of the Number) - Optics & Real Life Use ? | 7/26/2011 |
| Q: What i observe by looking at the Numeric Whole Numbers(Integers) in Mirror (Glass) Object are the ... A: I'd never thought about this before, but you've come up with a new set of numbers. I belive they ... | |
| Maths-Logarithm | 7/25/2011 |
| Q: Solve for x if x+log(1+2^x)=xlog5+log6...........the base is 10 for all log terms i.e for example ... A: This can be rewritten as log(10^x) + log(1+2^x) = log(5^x) + log(6). Since log(a) + log(b) = ... | |
| Continuity and differentiability | 7/18/2011 |
| Q: Differentiate (x^2-5x+8) (x^3+7x+9) in three ways mentioned below: (1) by using product rule. (2) by ... A: (1) The product rule says let f(x) = x^2 - 5x + 8 and g(x) = x^3 + 7x + 9. The derivative of ... | |
| Mathematics(logic) | 7/4/2011 |
| Q: 1. Some numbers are not prime. 2. No primes are squares. If "some" means "at least one", it can be ... A: 1. Some numbers are not prime. 2. No primes are squares. (C)some numbers are not squares. You're ... | |
| 3D vector | 7/4/2011 |
| Q: Suppose that three coordinate planes are mirrored and a light ray given by the vector a=(a1,a2,a3) ... A: To start off with, let's consider a two dimensional vector (a1,a2). If the slope were m and it were ... | |
| 3D vector | 7/3/2011 |
| Q: In 3 dimensional vector, the line segment from vector r0 to r1 is given by vector r= ... A: Take A as (0,10). Take B as (20,0). Take t as the numbers 0, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, ... | |
| Mathematics(logic) | 7/3/2011 |
| Q: 1. Some numbers are not prime. 2. No primes are squares. If "some" means "at least one", it can be ... A: (A) It does not state that any numbers are actually squares, eve though we know some are square. ... | |
| 3D vector | 7/2/2011 |
| Q: In 3 dimensional vector, the line segment from vector r0 to r1 is given by vector r= ... A: The equation is suppose to be on a line between r0 and r1. If we multiply r0 by a number t between ... | |
| 3D vector | 7/2/2011 |
| Q: In 3 dimensional vector, the line segment from vector r0 to r1 is given by vector r= ... A: Isn't the equation suppose to be r = (1+t)r0 + t*r1? Since this is an equation for a partial line ... | |
| Maths- Complex number | 7/1/2011 |
| Q: Find the real values of angle (theta) for which [(4+3isin(theta)]/[(1-2isin(theta)] is ... A: I tried varying thetat from 0 to 2*pi by in steps of pi/100. I quickly found that this was not even ... | |
| Maths- Complex number | 6/30/2011 |
| Q: Find the real values of angle (theta) for which [(4+3isin(theta)]/[(1-2isin(theta)] is ... A: The only values of theta that would work are 2*n*pi, for the sin(2n*pi) = 0. For any other values ... | |
| linearly independent rows | 6/29/2011 |
| Q: Is there any algorithm for matrix generation from/given the first row such that the matrix is ... A: The only condition that needs to be avoided is that the norm of the cross product of the rows is ... | |
| Limit | 6/26/2011 |
| Q: I have learned Limit theory of math well.but I have a basic question and that is why basically ... A: Limit and 0/0 occuring If we have x/x, this is cleary 1 everywhere but at x=0. However, since it is ... | |
| Functions | 6/23/2011 |
| Q: Let S={1,2,3,4,5} and consider the function 1subscript s from S into S defined by 1 subscript ... A: I'm not familiar with subscript used in this fashion, but I believe in this case it refers to a ... | |
| LOGARITHYMS | 6/22/2011 |
| Q: LOG BASE X 68 DIVIDED BY LOG BASE X 4 A: The log base a x divided by log base a y is log base y x. In other words, log base 2 64 = 6 since ... | |
| Maths-Trignometric ratio | 6/20/2011 |
| Q: Find the possible values of sinx If ... A: It is known that sinx is somewhere in [-1,1]. There is no specification for x, so it could be any ... | |
| Economics | 6/15/2011 |
| Q: can you please tell me what is the elasticity of demand when we have a demand curve of the form ln ... A: The elasticity of demand is how much change is expected in the quantity with respect to the price. ... | |
| Index | 6/15/2011 |
| Q: If 8(4^x-2^x)-2=2^(x+1) find x thanks ANSWER: (1) Remember, in this solution, that ln(b)/ln(a) = ... A: The equation is 8(4^x - 2^x) - 2 = 2^(x+1). Putting in x=0 gives 8(1-1) - 2 = 1, which is -2 = 1, ... | |
| Index | 6/13/2011 |
| Q: If 8(4^x-2^x)-2=2^(x+1) find x thanks A: (1) Remember, in this solution, that ln(b)/ln(a) = log(b) base a. (2) Also note 4^x = (2^x)(2^x) = ... | |
| Commercial math | 6/11/2011 |
| Q: One morning a fish monger bought 20kg of fish for #25 . By 11:30am he had sold 15kg of the fish at a ... A: He bought 20kg of fish for 2,500k. By 11:30, he had sold 15kg of fish at a profit of 60k per kg, so ... | |
| Trigonometry | 6/8/2011 |
| Q: Q. Prove the identity:- sin^3A + cos^3A/sinA + cosA + sin^3A - cos^3A/sinA - cosA = 2 A: That should be written as (sin^3A + cos^3A)/(sinA + cosA) + (sin^3A - cos^3A)/(sinA - cosA) = 2 ... | |
| number theory | 6/4/2011 |
| Q: Plzzzzzzz give a very difficult question in number theory so that I can practice A: I surveyed the last 100 questions I had, and I believe that last two questions I answered for you ... | |
| absolute value | 6/3/2011 |
| Q: How do I solve the following: a) abs(2y+4)=22-abs(6-2y) b) abs(x-1)-abs(x+2)<abs(x+1) A: The way to solve it is to note the critical values. In the first one, the critical values are found ... | |
| arithmetic | 6/3/2011 |
| Q: find the minimum number of terms that must be taken from the following sequence :8,16,24,32,.... so ... A: The series is 8 times the series 1, 2, 3, 4, ... Using this, the answer is 120, which is 8*15. It ... | |
| rule tables in algebra | 5/31/2011 |
| Q: I am attempting to help my daughter figure out the rule for this table and I am stuck...and so is ... A: Putting the table in order on the 'a' column is most useful. In order, it is A B 5 4 10 5 15 6 ... | |
| Radical equations in a word problem | 5/28/2011 |
| Q: I am not sure how to set up this problem at all, it is as follows: Solve the equation w= Cr^(-2) ... A: To solve for r, take w = Cr^(-2) and get r by itself. First, divide both sides byC, giving w/C = ... | |
| trig study guide,(im clueless) | 5/22/2011 |
| Q: Evaluate the sine, cosine, and tangent of the real number t = 7π/4. Find the exact value of ... A: Find the exact value of tan 21π using periodic properties. The trig function has period ... | |
| Trigonometry | 5/19/2011 |
| Q: Q. Prove that:- cos(pi/4 - x)cos(pi/4 - y) - sin(pi/4 - x)sin(pi/4 - y) = sin(x + y) A: I think I just accidentally hit the wrong button on this touchy computer. To answer this, note that ... | |
| Exponent | 5/15/2011 |
| Q: If 2^x=x^2 find x using the exponent(e) method A: Try various x. If x=1, 2^1 = 2 and 1^2 = 1, so that doesn't work. If x=2, 2^2 = 2^2 since both sides ... | |
| infinite geometric series | 5/11/2011 |
| Q: The question is find the sum, if it exists: infinity over sigma, (3/5)^k K=1. I know this looks ... A: If we took the sum for k = 0 to infinity of x^k, if |x|<1, that is 1/(1-x). Since we have x = 3/5, ... | |
| Standard Deviation | 5/1/2011 |
| Q: Heather works in a call centre assisting home-computer users. The average length of a call in her ... A: Her average is 605s. The last call, 569s, is 36 below 605s. The difference is 36 seconds. If being ... | |
| Year 10 Maths B | 4/30/2011 |
| Q: Sometimes it is impossible to get to the base of the tall object being measured, therefore it is not ... A: Using the drawing, the points A and B are two points on the ground. The angle between horizontal and ... | |
| Mean and Standard deviation | 4/29/2011 |
| Q: When reporting results to the office,Katty was told to make sure that the mean is 100 and the ... A: Use the normal distribution how many standard deviations between 106.5 and 100. Since the difference ... | |
| Probability | 4/28/2011 |
| Q: The probability of exactly four people out of ten having a blue ticket at a charity ball is ... A: Assume that the probability for one person is p, so to not get a blue ticket is 1-p. The chance of 4 ... | |
| Convergence | 4/25/2011 |
| Q: Can you tell me how to find out if a series of numbers converges? For example, a problem I had was: ... A: The problem is the series 7(4/5)^n for n = 0, 1, 2, 3, 4, ... Given a series n = 0, 1, 2, 3, 4, ... ... | |
| Probability | 4/24/2011 |
| Q: Approximately 76% of families in Toronto consist of married couples. There are 22 students in a ... A: Since the probability of living with a married couple is 0.76 and there are 22 students, it would be ... | |
| maths | 4/24/2011 |
| Q: How to find the number of solutions or ordered pairs (x,y,z) such that x*y*z=n .Where n is an ... A: The number 256 is 2 to the 8th. That means that 256 = 2*2*2*2 * 2*2*2*2 (with a space to count ... | |
| Probability | 4/22/2011 |
| Q: Jasmine looked at the results of an exam she had just given to her grade 2 science class. She saw ... A: The standarad deviation is the squareroot of the varance and measures the variability in data. Since ... | |
| Maths-Ellipse | 4/21/2011 |
| Q: Show that the line 3x+2y-8=0 touches the ellipse 3x^2+4y^2=16. Find the point of contact A: We have 3x + 2y - 8 = 0. Adding 8 - 2y to both sides gives 3x = 8 - 2y. Dividing both sides by 3 ... | |
| Circle | 4/17/2011 |
| Q: Write the followinng circle in standard form: 9x^2-6x+9y^2=170 A: I'd divide the whole equation by 9 1st, since the standard form has a 1 coefficient in front of x ... | |
| probability | 4/16/2011 |
| Q: In the game of craps. What is the probability of both the 5 and the 9 appearing before the 7? A: A 5 can appear as a 1-4, 2-3, 3-2, or 4-1, so there are 4 ways. A 9 can appear as a 3-6, 4-5, 5-4, ... | |
| Math | 4/15/2011 |
| Q: Is there any way i can learn the sine, cosine & tangent of any number without refering to four ... A: No, there is not, except for special angles. At 0 degrees, the sin is 0, the cosine ia 1, and the ... | |
| The Use of Probability | 4/13/2011 |
| Q: My math class has nearly finished our probability unit, and I honestly hate the subject. Why would ... A: I found it in http://wiki.answers.com/Q/Jobs_that_use_probability Many people used probability. ... | |
| Maths-ellipse | 4/12/2011 |
| Q: Find the equations of the tangent and normal to the ellipse x^2/25+4y^2/25=1 at the point in a ... A: The (abscissa, ordinate) is the same as (x,y). To have an ordinate of 2, this means that y = 2. To ... | |
| Core (proofs) | 4/11/2011 |
| Q: my teacher through the whole class for a loop with this question. Let A be a 4x4 matrix with ... A: I know that once a matrix diagonalized, the characteristic polynomial is given by the product of ... | |
| Function | 4/2/2011 |
| Q: Where can I find the graph of y=nCx.Sorry I wasn't clear the last time. Here nCx means n!/(n-x)!x! ... A: I write it with the C out fron, as in C(x,y). That is probably since that is the way a function ... | |
| Calculus | 3/31/2011 |
| Q: Let C:y=f(x)=ax^2+bx+c, xER, where a, b, and c are real constants with a different from 0. Prove ... A: I thought about the problem for so long that I forgot that we had to prove there were two tangent ... | |
| Maths | 3/28/2011 |
| Q: An old inclined sewer pipe has silted up and is to be renewed. It runs south at a bearing of 180° ... A: The current length of the 1st pipe is 140.54' and the 2nd pipe is 74.82'. The total length is ... | |
| Maths-Conic-Parabola | 3/14/2011 |
| Q: A circle having centre (4,-1)passes through the focus of the parabola x^2+16y=0.Show that the ... A: The center of the circle is given at (4,-1). The vertex of the parabola is at (0,0). Since the ... | |
| Precalculus - Volume of Cone Related Rates | 3/13/2011 |
| Q: A cone is made by cutting a sector of angle (theta) from a circle with a radius of 1 and gluing the ... A: The volume of a cone is πr²h/3 where r is the raidus and h is the height. To find the maximum ... | |
| college algebra | 3/10/2011 |
| Q: please show and answer a similar math type problem. if y varies directly as x, and inversely as m3 ... A: I'm not sure why it is m3 and r2 and not just m and r, so I'll go with that. So, if y varies ... | |
| Imaginary Quantities | 3/9/2011 |
| Q: Sir , imaginery numbers are those numbers which dont have real existence . So , why do we study ... A: I'm not sure I know of a real application of such numbers, but they do make for an interesting study ... | |
| Pre-Algebra | 3/6/2011 |
| Q: How do you get n=-11 fro the problem, "n+4n-22=7n"? Can you explain & show me step-by-step? A: The n + 4n on the left is 5n, so we have 5n - 22 = 7n. Subtracting 5n from both sides gives us 5n - ... | |
| Maths-Circle | 3/4/2011 |
| Q: If P(x1,y1)be a point of the circle x^2+y^2=2a^2,then prove that the two tangents drawn from P to ... A: The line from the center to the edge of the circle with radius a has length a. The line form the ... | |
| Function Rule | 3/3/2011 |
| Q: I am currently taking a class for elementary education teachers and one of the subjects we have ... A: I notice the numbers are very close to squares. That is, 0^2 - 1 = 0 - 1 = -1, 1^2 + 1 = 1 + 1 = ... | |
| pre-calculus | 3/3/2011 |
| Q: I have a question from college pre-calculus. Not sure if I can relay this without drawing it, but ... A: Let H = 6', W = 3', and D = sqrt(6^2 + 3^2) = sqrt(36+9) = sqrt(45). The point A will travel on the ... | |
| simplification | 3/2/2011 |
| Q: I am having some trouble with simplifying these equations, i have given them ago by myself and i ... A: It should be noted that 1) when 4 is cubed, it can be written as 4^3, so 4^3 = 4*4*4 = 16*6 = 64. ... | |
| math question | 2/27/2011 |
| Q: Show that there exist positive integers m & n such that 2^m - 2^n is a multiple of 2011 A: It is known that if m=n+1, them m² - n² = 2n+1. Since we have 2n+1 = 2011, 2n = 2010, and n = 1005. ... | |
| Percentage | 2/23/2011 |
| Q: Here is a simple multiplication calculation. 2 X 5 = 10 If the product, 10, represents 100% of the ... A: No. 20% times 50% is 10%, for 20% = 0.20 = 0.2 and 50% = 0.50 = 0.5, and 0.2*0.5 = 0.10. For ... | |
| Maths-Circle | 2/22/2011 |
| Q: Show that one of the two tangents drawn from (7,4) to the circle x^2+y^2-4x-12=0 is parallel to the ... A: To be tangent to the circle, the y value at the tangent point needs to be 4 and this value needs to ... | |
| Simplification | 2/21/2011 |
| Q: Hey there, just having some problems with my home work, and I cant seem to grasp or know how to do ... A: a. Exponets are multiplied together. That is, (5x²y)³ has exponets on x and y of 2 and 1. ... | |
| Sir, pls assist. Thanks. | 2/19/2011 |
| Q: 1) A restaurant charges $66 per person for a buffet dinner. For every 12 people, one will get it ... A: 1. If they paid $5610 and $66 gets a person in, then it can be seen that 5610/66 is the same as ... | |
| Discrete Math/Exponents | 2/16/2011 |
| Q: Use induction to prove 57 divides into (7^(n+2)) * (8^(2n+1)) for all positive integers n. I ... A: Take n=1. The first number is (7^3)(8^3) = 343*512, which would seem to be 175,616. It can be shown ... | |
| Complex Analysis | 2/15/2011 |
| Q: Let z=a+ib. Find the principle argument of the principle n-th root of z when a=2, b=4 and n=7. Give ... A: To compute the 4th root, convert the number to cyllindrical coordinates. Note that sqrt(x^2 + y^2) = ... | |
| Continuity | 2/14/2011 |
| Q: On what intervals is the function continuous? ln(x)/(inverse sin(x)) Thank you so much! A: The function ln(x) is continuous only for x > 0. The function inverse sin(x) is only good -1 < = x ... | |
| algebra rule | 2/13/2011 |
| Q: How do calculate the rule for the following: Somebody gets paid 1 cent on day 1, 2 cents on day 2, 4 ... A: Well, day 1 gives 1 cent, which is 2-1. Days 2 gives 2 cents, for a total of 3, which is 2^2 - 1. ... | |
| trigonometry equation | 2/13/2011 |
| Q: (1) If sin x = cos y, √6 sin y = tan z and 2 sin z = √3 cos x ; u, v, w denotes ... A: (1) If sin x = cos y, √6 sin y = tan z and 2 sin z = √3 cos x ; u, v, w denotes ... | |
| maths problems | 2/12/2011 |
| Q: I have resolved the problem. However I need you to assist on these 2 sums.Thanks 1) Xuxian and ... A: 1) Let x be the number of marbles. Rachel gives away 10, so she has x-10. Xuvian gives away 22, so ... | |
| trigonometry equation | 2/12/2011 |
| Q: 6 tan^2 x – 2 cos^2 x = cos2x if cos2x = ? A: Now cos2x = cos^2 x - sin^2 x and tanx = sinx / cosx. Putting these in gives 6[sin^2(x)]/[cos^2(x)] ... | |
| Sir, pls assist. Thanks a million!!! | 2/10/2011 |
| Q: 1)Mrs lee is 36yrs old & her daughter is 10 years old. In hw may years time, will Mrs. Lee be 3 ... A: 1) If Mrs Lee is 36 and her daughter is 10, in X years they will be 36+X and 10+X, respectively. We ... | |
| algebraic division | 2/7/2011 |
| Q: How do you solve? x root divided into 5.39 = 3.53 A: Do you mean 5.39/root(x) = 3.53? In that case, I use Excel after find what x should be. First, ... | |
| Functions Problem | 2/5/2011 |
| Q: I'm having trouble with this question...can you please help me? "You may have heard the fable about ... A: I put the problem in Excel. The 1st column is minutes passed, the 2nd column is how far the ... | |
| Probability | 2/3/2011 |
| Q: Approximately 76% of families in Toronto consist of married couples. There are 22 students in a ... A: Since there are 22 students and p = 0.76, 1-p = 0.24. To have exactly half living with a couple ... | |
| Maths-Circle | 2/3/2011 |
| Q: Find the equations of tangents to the circle 4x^2+4y^2=25 which are parallel to the X axis. A: A circle is expressed as (x-h)^2 + (y-k)^2 = r^2. Note that the center is at (h,k) and here, (h,k) = ... | |
| proving identites | 2/3/2011 |
| Q: i need to prove a problem and i am completely stuck. the problem is: (Sec-Tan)^2 = 1-sin / 1=sin ... A: It is known that sec = 1/cos and tan = sin/cos, so (sec-tan)^2 = ((1-sin)/cos)^2. This is the same ... | |
| statistics | 2/2/2011 |
| Q: The values of a,b,c in a quadratic a x2 + b x + c = 0 is determined by throwing an ordinary die with ... A: Using Excel, I found there were only 43 in this set of 216 choices with real solutions, which is ... | |
| Maths-Circle | 2/1/2011 |
| Q: Find the equations of the tangents to the circle x^2+y^2+2x-4y-8=0 at the points the sum of whose ... A: The equation of the circle would be found by completing the squares. That is, (x-a)² + (y-b)² = r². ... | |
| Probability | 1/31/2011 |
| Q: Children are sitting in rows in the theatre ready to watch a musical group perform. In the fourth ... A: Yes, despite the fact I made an error and said 120/6 = 10, for it is really 120/6 = 20. From the ... | |
| Probability | 1/30/2011 |
| Q: Children are sitting in rows in the theatre ready to watch a musical group perform. In the fourth ... A: There are 6 10th graders, 8 11th graders, and 11 12th graders. To be won by people in the same grade ... | |
| Trigonometry | 1/29/2011 |
| Q: y= a(cosec(x/2))-b, 0≤x≤2π, 0≤y≤5 and cosec(x)=1/(sin x) find a and b ... A: Putting in the point (π/3,2) gives 2 = a/sin(π/6) - b. Since sin(π/6) = 1/2, and 1 ... | |
| probability | 1/28/2011 |
| Q: one hundred and thirty circular cylinders are stacked in the row in such a way that the number in ... A: One possibility is the the 2nd row contains 15, and 15+16 = 31, the 3rd row contains 14, and ... | |
| Pre calc | 1/26/2011 |
| Q: A manufacturer of metal widgets make two types, A and B. Each type A widget requires 0.5 hours of ... A: A) 0.5, 1.5, 1.0 B) 0.5, 1.0, 1.5 Total) 15, 36, 42 Profit for A, B is $3, $4 Since A and B both ... | |
| linear algebra | 1/25/2011 |
| Q: Given the vectors u =(1,2,3) and v = (2,3,1) in R3: a. Find k so that w = (1,k,6) is a linear ... A: a. Given two variables w and v, we need wx + vy = (1,k,6). That is, for the x part, u is 1 and v is ... | |
| Modulus Functions | 1/25/2011 |
| Q: I was doing an ALevel Cambridge past papers and i got thisSolve the Inequality |2^x - 8| < 5 . ... A: The absolute value is always positive. If 2^x - 8 is negative, the absolute values is 8 - 2^x, ... | |
| word problems- polyomials | 1/24/2011 |
| Q: The cost of doing business for a company can be found by adding fixed costs, such as rent, insurance ... A: I'm not sure I understand the question, since, according to what I get, 0, 20, and 25 tiles all ... | |
| Maths-Circle | 1/21/2011 |
| Q: Find the equations of two circles each of which passes through(1,2) and touch both the co-ordinate ... A: A lot of times when I get a problem, I'm not really thinking about it but I really am, for now I see ... | |
| Reincarnation | 1/20/2011 |
| Q: Is reincarnation a mathematical impossibility? A: From personal experience, I can testify that we only have one chance to live and at the end, we meet ... | |
| Maths-Circle | 1/19/2011 |
| Q: Find the equation of the circle having radius 4 and touching the X-axis at (3,0) A: When it says touching the X-axis at (3,0), I assume that means touching and not crossing. From the ... | |
| Maths-Circle | 1/18/2011 |
| Q: Find the equations of two circles each of which passes through(1,2) and touch both the co-ordinate ... A: Actually,looking back at it, I gave two circles who have a cenert at (1,2). To make a circle touch ... | |
| Maths-Circle | 1/18/2011 |
| Q: Find the equation of the circle passing through the origin,having radius 5 and the sum of the ... A: The equation of a circle with radiius 5 and center (x0,y0) is (x-x0)^2 + (y-y0)^2 = 25. It also ... | |
| Linear Programming | 1/16/2011 |
| Q: In order to solve linear programming problems we consider only corner points of feasible region. Why ... A: Since we have a linear programming problem, consider a solution set x so that x is not on a border. ... | |
| Trig Functions | 1/10/2011 |
| Q: sin(a) + sin(b) = .90154 cos(a) + cos(b) = 1.6448 solve for a and b A: I don't know of any way to find a and b exactly, but maybe approximation would work. Guess at the ... | |
| Lottery Probabilities | 1/9/2011 |
| Q: In a 6 in 49 lottery, if I were to choose only odd numbers, am I equally likely to win the lottery ... A: 1st, I will say that C(a,b) = a!/(b!(a-b)!). The chance of them all being odd is C(49,25). The ... | |
| Maths-Linear inequations | 1/8/2011 |
| Q: A dealer can sell two types of cloth A and B.He can sell at the most 400 units of A and 300 units of ... A: Since he can't see more that 400 units of A, the inequality is A <= 400. Similarly, B <= 300. Since ... | |
| Modulus functions | 1/7/2011 |
| Q: I understand clearly what y=|x+1| means, but what about |y|=x+1 ? I have tried drawing y modulus ... A: To draw this curve, draw y = x + 1, which has slope 1 and intersects the y-axis at 1. The absolute ... | |
| Maths-Combination | 1/4/2011 |
| Q: The letters of the word "BRONZE" are written in all possible order .How many words are possible?.If ... A: The first word would be the letters in alphabetical order. That would be BENORZ, then BENOZR, then ... | |
| Practicalities | 1/4/2011 |
| Q: So I've completed my high school mathematics. I've done equation after equation, most pertaining to ... A: After the basics of algebra, geometry, and trig, there is a whole lot more math. For example, given ... | |
| Maths-Combination | 1/1/2011 |
| Q: The letters of the word "BRONZE" are written in all possible order .How many words are possible?.If ... A: There are 6 letters in BRONZE, and all of them are unique, so there would be 6 ways of choosing the ... | |
| Probability | 12/28/2010 |
| Q: Could you please help me with the following question? What is the probability that out of 23 ... A: I know a way to do it that is much easier than trying to follow the hint. Calculate the probability ... | |
| precal | 12/27/2010 |
| Q: polynomial 2x^4 - 16x^2 - 18 write in factored form A: The first thing to do is to take t = x^2 and get 2t^2 - 16t - 18, and then factor that quadratic. ... | |
| Linear Equation | 12/26/2010 |
| Q: Word Problem- The sum of 2 digits of a 2 digit number is 12. When 18 is added to it the digits are ... A: Let the digits be x and y, so the number is 10x + y. When the digits are reverse, the number if 10y ... | |
| Maths-permutation | 12/25/2010 |
| Q: "Out of 8 consonants and 4 vowels how many words of 3 consonants and 2 vowels can be formed" A: Choosing the consonants would be 8 choose 3, of 8*7*6/3*2 = 56. Choosing the vowels would be 4 ... | |
| Maths-Combination | 12/25/2010 |
| Q: Plane consists of 25 straight lines ,no two of them being parallel and no three of them being ... A: Note that the nth line has n-1 lines already there, and it crosses all of them. This makes 2 lines ... | |
| Gasoline Prices | 12/23/2010 |
| Q: When gasoline prices are posted on signs at businesses that sell gas, the price is listed with a ... A: They post it that way since when I was growing up gas use to cost around 30 cents and the actual ... | |
| Advanced Math | 12/21/2010 |
| Q: I am writing a short story for a class, and in it, the main character has to answer a college level ... A: Let the total snow flakes be 100. The variables are Ss, Sl, and St, for Sam, Lisa, and Tom, ... | |
| Maths-permutation | 12/18/2010 |
| Q: A boy has 3 library tickets and 8 books of his interest in the library of these 8 books ,he does not ... A: It looks like there are 8 books to choose from. The condition is one book can't be borrowed without ... | |
| Maths-Permutation | 12/18/2010 |
| Q: How many Quardratic equations can be formed with the coefficients 0,5,7,9(coefficients may be ... A: The only requirement to make it a quadratic equation is that the coefficient on x² must be posivite. ... | |
| Pre-Calculus | 12/16/2010 |
| Q: Write this function as cosine of angle, cos65°cos50°+sin65°sin50°. A. cos(50°) B. cos(15°) ... A: Given the equation cos(65°)cos(50°) + sin(65°)sin(50°), the first thing to come to mind is cos(A+B) ... | |
| Maths-Permutation | 12/15/2010 |
| Q: In how many different ways can the letter of the word "ARRANGE" be arranged ,if besides the two R's ... A: There are 7 letters. The 1st letter can be put in 7 positions, the 2nd letter can be put in 6 ... | |
| Vectors and Bearing Pre-calculus | 12/15/2010 |
| Q: You swim at 4kph with your body perpendicular to a stream. But because the water is moving, your ... A: You are swimming at 4kph, and I'll call this A. Call the current's rate B. Call the actual speed of ... | |
| Maths-Permutation | 12/14/2010 |
| Q: How many different words can be formed with the letter of the word "DIPAWALI".In how many ways "P" ... A: Think about it - if there were two letters, say AB, there would be two ways - AB or BA. If there ... | |
| Function Rules of Math | 12/14/2010 |
| Q: Input output Tables. I need the equation if x= 0,1,2,3, and y= 7,21,35,49. i do not quite ... A: The best way to do these kinds of problems is to look at the differences. Notice that x goes from 0 ... | |
| Conics | 12/12/2010 |
| Q: Write the equation for ellipse in standard form: Foci at (0,0) and (0,8), sum of the focal radii ... A: The formula for an ellipse is [(x-h)/a]² + [(y-k)/b]² = 1 where (h,k) is the center. The constants ... | |
| poynomials | 12/12/2010 |
| Q: Can you factor the following polynomials? 1.9 - x^2 2.4x^2 + 81 - 36 3. 4y^2 + 16y 16 4.x^2 ... A: You can factor 1, 2, 3, and 4. In fact, here's the answers. 1. (3-x)(3+x) 2. First, a 4 can be ... | |
| Problems involving quadratic equations | 12/9/2010 |
| Q: I have been given the quadratic equation Tickets= -0.2x^2+12x+11 which is supposed to model ... A: Using the quadratic equation, the two places where the equation would be 0 can be found. Using ... | |
| Combinatorics | 12/8/2010 |
| Q: Teddy is in a hurry to tidy up.Without looking at the case of 3 CDs,Teddy just puts the CDs into the ... A: There are 3 cases for the 1st CD, 2 for the 2nd CD, and only 1 case for the 3rd CD. This gives a ... | |
| Mathematical Induction | 12/8/2010 |
| Q: My problem is to prove the inequality (3n+20)<(3^n) for all n>=4. The Basis step is obviously easy ... A: I would start out by showing 3*4 + 20 < 3^4. This is since 3*4 = 12, and +20 = 32 for the left and ... | |
| Math Help | 11/30/2010 |
| Q: I am really weak in math, and i need help with systems of eq. and elimination. 5p+4q-14=0 ... A: Divide the 2nd equation by 15, and get p = -33/15 + 3q/15. Put this value of p in the 1st equation, ... | |
| Combinatorics | 11/30/2010 |
| Q: Mr.Scott, Did you recieve my question today? If you did and solved it than probably I ... A: I got your question, I answered it, and it was sent back to the computer from which it was given. ... | |
| Combinatorics | 11/29/2010 |
| Q: No. of ways of selecting 4 people from 12 people is the same as the no. of ways of selecting 8 ... A: This is selecting M people out of N. The formula is N choose M, which is N!/(M!(N-M)!), where '!' is ... | |
| 4th grade advanced math | 11/29/2010 |
| Q: I need to find an equation that will work for x and y with x = 1,2,3,4,5,6 and y = 8, 15, 24, 35, ... A: There is something called difference tables where the 1st column is x and the 2nd column is y. ... | |
| Maths-trignometry | 11/20/2010 |
| Q: If triangle ABC is right angled at c prove that b=c-c(sinA).tan(A/2) A: On the right side, factor out c, giving c(1 - sinA*tan(A/2)). Note that tan(A/2) = sinA/(1+cosA), ... | |
| Mathematics (Probability) | 11/19/2010 |
| Q: What is the probablity of getting |x|<2 from a group of numbers i.e -3,-2,-1,0,1,2,3 options??????? A: First, let's count the choices. There are 3+1+3 = 7 choices for the x value. Let N=7. Next, let's ... | |
| Trigonometry | 11/18/2010 |
| Q: what is the principle calculator value rounded to two decimal places for sec x = 2? A: Since sec x = 1 / cos x, this means that cos x = 1/2. For the near side to be half of the diagonal, ... | |
| Algorithm | 11/15/2010 |
| Q: Please see the attached JPG file. Thanks A: // written in C++ #include <stdio.h> int exp(int n) { int i=0; // counter while ((n % 2) == ... | |
| Maths | 11/15/2010 |
| Q: Find function for X values 1, 3, 5, 7 Y values 3, 6, 11,18 A: Construct a difference table. It looks like 1 3 3 6 3/2 5 11 5/2 1/4 7 18 7/2 1/4 0 The ... | |
| higher level mathematics | 11/12/2010 |
| Q: how to solve the equation log6(5W)*log2(p+3)=11 A: Note that log6(5W)*log2(p+3) = 11 can be converted to log6(5W) = 11/log2(p+3). Now since loga(b) = ... | |
| math | 11/11/2010 |
| Q: Which is bigger & why? 16^18 or 18^16 A: Look at 16. It is 2^4, and this make 16^18 into 2^(4*18), which is 2^72. It is known that 18 is ... | |
| Solving Linear Equations | 11/7/2010 |
| Q: If you need to solve large systems with more than three variables, which method is more efficient ... A: Cramer's rule is true and works in theory, but for solving anything bigger than a 3x3, it is very ... | |
| Precalculus | 11/6/2010 |
| Q: The sprockets and chain of a bicycle measures are as follows. The pedal sprocket has a radius of 4 ... A: We are given pedal sprocket: 4 inch radius; wheel sprocket: 2 inch radius; entire wheel: 13 inch ... | |
| trig word problem | 10/18/2010 |
| Q: From an observation tower that overlooks a runway, the angles of depression of point A on one side ... A: I think I answered this already, but here's another approach. The distance from A to B is 1.1 km. ... | |
| algebra | 10/17/2010 |
| Q: Solve algebraically: 1) 3 square root of x - 5= 3. 2) x(3/2 =27. 3) 3/4=1-3x-2/x+1 A: 1) If it sqrt(x) - 5 = 3, then sqrt(x) = 8, so x = 64. If it is sqrtqrt(x-5) = 3, x-5 = 9, so x = ... | |
| Volume of metal in a pipe | 10/16/2010 |
| Q: Pipe is 2.5cm thick, 2m in height and 40cm in diameter Volume of metal using (pi x r1 x r1 x h)- ... A: It is different because the radius on the insides of the pipe is smaller than the radius on the ... | |
| absolute value functions and graphs | 10/14/2010 |
| Q: I'd like to ask for help on how to go about answering the following questions. Suppose you pass St. ... A: Make each city block 1 square. Mark where St. Aloysius church as a point somewhere on the positive ... | |
| Precalculus | 10/12/2010 |
| Q: The sum of two numbers is twice their difference. The larger number is 4 more than twice the ... A: The numbers are x and y. It is given that x+y = 2(x-y) and x = y+4. Simplifying the 1st equation ... | |
| Table of Values & Rules | 10/7/2010 |
| Q: I have to find the value of n, where i have the values for x and y: x = 0, 1, 2, 3, 4 and y = 10, ... A: Note that the x values all step up by 1 each time from 0 to 1 to 2 to 3 and then to 4, so they ... | |
| Precalculus | 10/6/2010 |
| Q: Could you please help me with this problem? Thanks. Find a polynomial function with real ... A: When the zeros of a function are given as x1 and x2, the function is K(x-x1)(x-x2) for some constant ... | |
| A X ( B U C) Discrete Math Help | 10/6/2010 |
| Q: A X (B U C) A= A,B,C B= C,D,E C= A,C,X How would I go about solving A X (B U C) Could you ... A: Now it looks like A is {A,B,C}, B is {C,D,E}, and C is {A,C,X}. It can then be seen that to join B ... | |
| Mathematics question | 10/3/2010 |
| Q: Solve the set of the simultaneous equations in R: x+y = π/2 sin x + sin y = 6 "to the power ... A: Is that x+y = π/2 and sin x + sin y = 1/z, where z^2 = 6, z>0? Since x+y=π/2, siny = ... | |
| math | 10/2/2010 |
| Q: in the following questions,question 1 x=vt, if x is measured in meters and t is measured in seconds, ... A: 1. The value of v will be in meters/second, and is written as m/s. Thus, the untis on the equation ... | |
| word problems/demand equation | 10/1/2010 |
| Q: Suppose a market research company finds that a price of p=$20, they would sell x=42 tiles each ... A: Well, at $20 there would be 42 and at $10, there would be 52. By a drop in $10, 10 more would be ... | |
| functions | 10/1/2010 |
| Q: I cannot find the rule from the follwing table. Please help. x=0,1,2,3 y=1,1.5,2,2.5 Thank you. A: First, look at the changes in x. They are 1 - 0 = 1, 2 - 1 = 1, and 3 - 2 = 1, so all of them are 1. ... | |
| Complex Analysis | 9/23/2010 |
| Q: may i get some leads on how to go about this question please? googled lecture notes and txtbooks but ... A: I referred to www.kith.org/logos/things/euler.html I also used the fact fact the ln(ab) = ln(a) + ... | |
| demand, revenue, & profit | 9/21/2010 |
| Q: You operate a gaming Web site, www.mudbeast.net, where users must pay a small fee to log on. When ... A: Since there are only two points given, a line might be what to find. The two points would be ... | |
| critical points | 9/20/2010 |
| Q: find all the critical points of the function f(x,y) = 2 + 4x - (x^3)/3 - x(y^2) - (17(y^2))/2 + ... A: It can be seen that ∂f/∂x = 4 - x² - y². Setting this equation to 0 means that is y is ... | |
| statistics | 9/18/2010 |
| Q: METHOD 5 Simple moving average A simple moving average (SMA) is the unweighted MEAN of the ... A: I would do a forecast by noting the average increase for each year/ The increases are 20, 20, 10, ... | |
| Maths | 9/18/2010 |
| Q: Solve for x in |(1)/(x-3)| < |(x)/(x-2)| A: In the first interval, the left side of the equation has a negative term in the absolute value, so ... | |
| Advanced - Linear algebra - Induction | 9/17/2010 |
| Q: This is a hard question that needs to be completed using the principle of mathematical induction, ... A: There are three things to note about this problem which show that the left side is greater. 1 – ... | |
| vector spaces | 9/15/2010 |
| Q: (a) Let w = (1 2 3). Let V be the set of all vectors v is R3 such that w.v = 0. Prove that V is a ... A: (a) Take w = (wx,wy,wz) and v = (vx, vy,vz). Since w = (1,2,3), w•v is known to be 1*vx + 2*vy + ... | |
| Prove sinx cosx | 9/15/2010 |
| Q: Prove that (tanx-1) (sin2x-2cos squarex) = 2(1-2sinx cosx) A: First, note three properties of trig: 1) tanx = sinx/cosx, 2) sin2x = 2sinx*cosx, and 3) sin²x + ... | |
| spherical expansion | 9/14/2010 |
| Q: For any point on the surface of a sphere expanding at a constant volumetric rate, what are the ... A: The problem states that dV/dt = K. It is known that dV/dt can be expanded to dV/dt = (dV/dr)(dr/dt). ... | |
| Precalculus: Difference Quotients | 9/14/2010 |
| Q: f(x)=x^2-x+1 and i have to find f(2+h)-f(2)/h A: If 2+h is put in f(x) for x, the result is (2+h)² - 2-h + 1. That reduces to 4 + 4h + h² - 2- h + 1, ... | |
| Sovling Systems Of Equations In Three Variables | 9/12/2010 |
| Q: Sometimes I just don't know where to start... x + y + z = 3 13x + 2z = 2 -x - 5z = -5 A: Note that the 2nd and 3rd equati have equations only have x and z. Using the 3rd equation, it can be ... | |
| probability topic | 9/12/2010 |
| Q: The percentage of batteries supplied to a retailer by Factories A and B are 75% and 25% ... A: From what given, from factory A, 1% of 75% is defective, and that is 0.01*0.75. Now when those are ... | |
| Linear Algebra (System of Linear Equations) | 9/11/2010 |
| Q: Mr. Wilson, I appreciate the time you put in to help with questions like mine. I have a question ... A: Solve the 1st equation for x. This gives x = 1 - y + z. Put the solution into the 2nd and 3rd ... | |
| division | 9/11/2010 |
| Q: I was taught in high school that any integer divided by zero equals 1. x/0=1. Got a beer riding on ... A: Then the teacher was wrong. To look at this, look at 6/2. Now 1x2 = 2, and that's not enough. Next, ... | |
| Functions | 9/9/2010 |
| Q: Determine whether f is a function from Z to R if: A: f(n)= ±n. B: f(n)= √(n^2+1) C: f(n)= ... A: A. Since there is a ± involved in the value, it is not a function. Functions only have one value at ... | |
| finding a formula for a function table | 9/8/2010 |
| Q: here is the table, could you help me with the formula that goes with it? x=1,2,3,4 y=1,7,19,43 ... A: The best way is to make a diffence table with x, y, and the diffenerences. It looks like 1 1 2 ... | |
| mixture problem | 9/7/2010 |
| Q: what quantity of a 60% acid solution must be mixed with a 30% solution to produce 300 ml of a 50% ... A: We know that there are 300 ml. Take x of the 60% solution. This means that (300-x) is of the 30% ... | |
| locus | 9/5/2010 |
| Q: How would I go about finding the locus of all points equidistant from the point F(-6, 3) and the ... A: A point in the locus is (x,y). The abs(x) is the absolute value of x. The distance to the point ... | |
| Quantitative Analysis for Managerial Applications | 9/3/2010 |
| Q: 1. Among the examinees in an examination 30%, 35% and 45% failed in Statistics, in Mathematics, ... A: Q1. Failure rate is 30% Statistics 35% Mathematics 45% in Statistics and/or Mathematics. Since 30% ... | |
| Quantitative Analysis for Managerial Applications | 9/3/2010 |
| Q: From a set of 1000 observations known to be normally distributed, the mean is 534 cm and SD is 13.5 ... A: Take (561-534)/13.5, which is 2. To exceed 561 is the same as a normal distribution being over 2 ... | |
| pre-calculus word problems | 9/2/2010 |
| Q: A 21m by 25m rectangular garden is to have a gravel path of uniform width bordering it. How wide is ... A: The total path has width w. The are of this path would be 21w + 25w + 21w + 25w + 4w². That is 4w² + ... | |
| Pre Calc Trig functions | 8/30/2010 |
| Q: I need help on my Pre calc trig homework... f(x)= 4 F(x)-f(7) x+1 x-7 ... A: Given that f(x) = 4/(x+1), find [f(x) - f(7)]/(x-7). Note that f(7) can be found by 4/(7+1) = 4/8 = ... | |
| Discerete Maths | 8/30/2010 |
| Q: True or False? If true, give proof; if false give counterexample for all Int a.b.c.e, a|(b+c) ... A: That looks like: Given a is divisible by b+c, this means that a is divisible by b or a is divisible ... | |
| Inverse Fractions | 8/5/2010 |
| Q: Is it possible to find the inverse fraction of 2 and 1/3 without first changing it to an improper ... A: The way to make sure is to eliminate all plus and minus signs. Note that 2 1/3 is realy 2 + 1/3. ... | |
| complex numbers | 8/5/2010 |
| Q: What is the fourth root of 7 + 24i A: To compute roots of complex numbers, first convert them to polar. Here, x=7 and y=24. In polar we ... | |
| Inverse Fractions | 8/4/2010 |
| Q: Is it possible to find the inverse fraction of 2 and 1/3 without first changing it to an improper ... A: It is not possible to find the inverse of 2 1/3 without saying that it is 7/3, so the inverse is ... | |
| Heads and a half or tails? | 8/3/2010 |
| Q: If I had a biased coin which landed 60:40 and could bet on it - what would be the ideal percentage ... A: It would be good to have your address to send you the file. Here it is in the proper format to be ... | |
| Help with Algebra Questions.. | 8/3/2010 |
| Q: I'm so confused, please help and explain. 1.Find all real solutions of the polynomial equation: ... A: Yes, the answers are 3, 3, and 3 since the polynoimal f(x) = (x-3)(x-3)(x-3). On 2, I found it ... | |
| Help with Algebra Questions.. | 8/2/2010 |
| Q: I'm so confused, please help and explain. 1.Find all real solutions of the polynomial equation: ... A: 1. Find all real solutions of the polynomial equation: f(x) = x^3 - 9x^2 + 27x - 27 Note that cubics ... | |
| Heads and a half or tails? | 8/2/2010 |
| Q: If I had a biased coin which landed 60:40 and could bet on it - what would be the ideal percentage ... A: It just seemed like a good amount to me. I calculated the expected amount of money given that the ... | |
| Reducing the cubic | 8/1/2010 |
| Q: Good afternoon Scott, I'm having some problems reducing the cubic and wondered if you could help at ... A: We take (y + r)^3 + b(y + r)^2 + c(y + r) + d = 0. Now (y+r)^3 = y^3 + 3y^2r + 3yr^2 + r^3, ... | |
| algebra | 7/30/2010 |
| Q: I am stuck on these,Please help. The magnitude and direction of vectors u and v are given. Find ... A: It is known that (x,y) = (rcosΘ,rsinΘ). 1. Converting u to 2u gives magnitude 30, angle ... | |
| Trig | 7/29/2010 |
| Q: Find all the solutions of the equation cos 2θ = sin θ on the interval 0 ≤ θ < ... A: Since cos 2Θ = 2 - sin²Θ, this is 2 - sin²Θ = sinΘ, which is rewritten as ... | |
| SET THEORY | 7/28/2010 |
| Q: In a group of 50 students,there are 30 males and 40 vegetarians and 25 male vegetarians .find the ... A: a) If there are 50 students and 30 males, this means the number of females is N where N = 50 - ... | |
| polar equation | 7/28/2010 |
| Q: What geometric figure results from the following polar equation? Give the rectangular form of the ... A: We are given that r = -2cosΘ. It is known that x² + y² = r² and tanΘ = y/x. The far leg is ... | |
| Maths-SETS | 7/27/2010 |
| Q: In a hostel ,25 students take tea ,20 student take coffee,5 student take milk,10 student take both ... A: The numbers are tea: 25 coffee: 20 milk: 5 tea & coffee: 10 milk & coffee: 8 Now since there are ... | |
| calculus | 7/26/2010 |
| Q: How do I solve for x?: 2^x+1= 3^x A: This must be 2^(x+1) = 3^x, so take the ln of both sides. This is ln(2^(x+1)) = ln(3^x), and the ... | |
| math/probability | 7/22/2010 |
| Q: A lawsuit has a 50% chance to be won by the plaintiff for some amount (and therefore -0- 50% of the ... A: I thought I answered this, but here's the answer again. This can sort of be done with math, but its ... | |
| Algebra | 7/21/2010 |
| Q: H) In your own words, explain the first condition that must be met for a simplified radical. Explain ... A: H) The radicals need to always be in the numerator to be a simplified number. Multiply by ... | |
| Depreciation and Logs | 7/19/2010 |
| Q: The number of years n for a piece of machinery to depreciate to a known salvage value can be found ... A: Using n = (lg s - lg a)/(lg(1-r)), we get n = (lg 10,000 - lg 100,000)/lg(1-0.10). Now since log b - ... | |
| Discrete Math | 7/17/2010 |
| Q: Prove the given property of the Fibonacci numbers for all n is greater than or equal to 1. (Hint: ... A: The Fibbonaci numbers are 1, 1, 2, 3, 5, 8, 13, 21, ... each where the next one is the sum of the ... | |
| Annual Percentage Yield | 7/15/2010 |
| Q: Do you know how to determine the APY annual percentage yield by using another calculation than APY = ... A: The best way is to known r and n, and then compute r/n, add to 1, take to the n, and subtract 1. A ... | |
| Discrete Math | 7/15/2010 |
| Q: State which proof technique you should use to prove the following assertion: if the product of two ... A: I would use the contradiction. Call the product of the two numbers z, the two numbers x and y, and ... | |
| Discrete Math | 7/13/2010 |
| Q: A colony of bats is counted every two months. The first four counts are 1200, 1800, 2700, and 4050. ... A: 1. Note that 1800/1200 = 18/12 = 3*6/2*6 = 3/2 = 1.5. Next, take 1.5* 1800 = (3/2)1800; 1800/2=900, ... | |
| proofs | 7/12/2010 |
| Q: I am really having a hard time knowing where to start on this problem. If T is a right triangle with ... A: Start with the left side, which is (c^6 - a^6 - b^6)/3. Note that c² = a² + b², so that c^6 = (c²)³ ... | |
| Proving Identities, Complex numbers | 7/11/2010 |
| Q: I need to prove the following: cos^2 x-sin^2 x = 1-2 sin^2 x using only this information: cos x = ... A: Add sin²x to both sides of the equation, giving cos^2 x = 1 - sin^2 x. Notte that cos²x = (e^2jx + ... | |
| co ordinate geometry | 7/10/2010 |
| Q: Two vertices of an isosceles triangle are (2,0) and (2,5).Find the third vertex if the length of ... A: Since the vertexes are (2,0) and (2,5), the length of the base of this isosceles triangle is 5-0=5. ... | |
| complete factoring | 7/10/2010 |
| Q: I really need help on my complete factoring while u solve it can you also explain how to do it? ... A: Note what the factors are of the first number and the last. The sum of the product is the same as ... | |
| Properties of Logarithms | 7/8/2010 |
| Q: I'm totally lost. I can follow how they do it in the book, but when I try to do one on my own I just ... A: The definition of a log is the power needed. For example, since 3^4 = 81, log3 81 = 4. 1. Note that ... | |
| Calculus | 7/7/2010 |
| Q: "Find the equations of the tangent line and the normal line to the curve (x^2+y^2)^2 =(x-y)^2 at the ... A: It says that (1,-1) is on the curve. To check and make sure, we put (1,-1) in as (x,y), and the ... | |
| The odds in #'s | 7/5/2010 |
| Q: Would anyone's chances of winning the lottery be higher or lower if they played the same numbers ... A: The choice of numbers in the lottery is random, so that chance of picking the same set of numbers as ... | |
| math | 7/2/2010 |
| Q: What is the function rule that represents the relationship between x and y? x=.5, y=2,x=1 ... A: To organize the values, put them in columns. That is, x y 0.5 2.0 1.0 1.0 2.0 0.5 4.0 0.25 ... | |
| Intermediate Algebra Questions | 7/1/2010 |
| Q: We had a test in my intermediate algebra class today. On it was this1.)A marching band has 52 ... A: The people must be grouped into groups of two groups. The 1st group has n(6B+P). The 2nd group has ... | |
| distance question | 6/20/2010 |
| Q: I went 4 miles to west and then 2 miles to north west. How many miles did i go? A: The way to do problems with angles that are not 90° is a modified formula. The sides are a, b, and ... | |
| formula from curves for two inputs | 6/19/2010 |
| Q: I need your help in this matter, the discription of the subject is: we have two input vectors ( ... A: Put the data in a scpreadsheet and view an x-y graph. A linear approximation would be the one that ... | |
| Discrete Math | 6/18/2010 |
| Q: Prove or disprove the following statements 1. For every positive integer n, 2n+1 is prime1. 2. ... A: 1. False. Take n=4. This makes 2n+1=9. It is known that 9=3*3, and this is not prime, so it is ... | |
| Discrete Structures | 6/17/2010 |
| Q: Using the predicate symbols shown and appropriate quantifiers, write each English language statement ... A: I take it the promlem P(x) is ”x is a person.” T(x) is ”x is a time.” F(x,y) is ”x is fooled at y.” ... | |
| Discrete Math | 6/16/2010 |
| Q: What inference rule was used in the following arguments 1. If the car was involved in the ... A: Is this what you're looking for? I haven't seen this stuff in over 25 years, so I'm not quite sure ... | |
| Discrete Structures | 6/16/2010 |
| Q: 1 . 1! + 2 . 2! + 3 . 3! + ... + n . n! = (n+1)! - 1 where n! is the product of the positive ... A: That is, 1*1! + 2*2! + 3*3! + ... + n*n! = (n+1)! - 1. 1. The base case is where n=1. Thus, we ... | |
| Discrete Structures | 6/14/2010 |
| Q: Show that if n is an integer and 3n+2 is even, then n is even using: (4 points) 1. a proof by ... A: 1. If n is an even number, it can be written as 2m, where m is an integer. 3n + 2 is then 3(2m) + 2, ... | |
| Finding the rule for a function tabel | 6/11/2010 |
| Q: I can't get either of these two problems x=-1,1,5 y=-10,-8,-4 or x=0,1,2 y=1,1.75,2.5 please help ... A: For the first one, look at the difference between x and y. -10- -1 = -9. -8 - 1 = -9. -4 - 5= -9. ... | |
| Need Geometry Help Urgently! | 6/10/2010 |
| Q: and good evening. My name is Charles, and I am an 8th grade student taking Honors Geometry. I need ... A: When points A and D have been picked and are on the diameter of a circle, B is on the circle since ... | |
| Future Value & Compound Interest | 6/10/2010 |
| Q: I have a question regarding the following compound interest and future value calculation. Year 1 P ... A: Not that P can be factored out of P+rP+ r(P + rP). This gives P((1+r)+ r(1+r)) = P(1+r)(1+r) = ... | |
| geometry/measurement-length | 6/9/2010 |
| Q: What number of feet is equivalent to 725 dam rounded to the nearest thousandth? A: From what I found, dam refers to a decameter. A decameter is 10 meters. That is 32.808 feet, ... | |
| Verifying Trig Identities | 6/8/2010 |
| Q: How do I verify these trig identities? cosx/1-sinx=secx+tanx and 1+cosx+sinx=2cscx and ... A: FOR cosx/(1-sinx) = secx + tanx... sol'n) For cosx/(1-sinx) = secx + tanx, multiply the top and ... | |
| x | 6/6/2010 |
| Q: ln(x)=e^(-x) What is the value of x? A: The function ln(x) and e(x) are inverses of each other. To find the solution, use Excel. I used 2 ... | |
| Future Value & Compound Interest | 6/4/2010 |
| Q: I have a question regarding the following compound interest and future value calculation. Year 1 P ... A: Expanding (1+r)^n has factors that are found in what is called Pascal's triangle. The top row (n=0) ... | |
| Question on Permutation & Combination | 6/1/2010 |
| Q: In how many ways can 4 balls be put in 5 boxes if a)the balls are the same color and the boxes are ... A: a) The ways to do it are: [1] all the balls can all be put in one box, [2] three can be put in one ... | |
| PreCalc | 6/1/2010 |
| Q: The motion of an oscillating weight suspended by a spring was measured by a motion detector. The ... A: (a) The approximate amplitude is the observed max - observed min where they are both measured on the ... | |
| Word Problem with vectors | 5/31/2010 |
| Q: - To fly due north at 580km/h when there is a 45km/h wind blowing from 130degrees, with what heading ... A: Both of these follow the rule a² + b² = c² - 2abcos(C), where C is the angle between sides a and b. ... | |
| math | 5/30/2010 |
| Q: I wonder if you could help me with a problem associated with my pastime of geocaching. If you ... A: Apparently I misread the question. Sorry about that. To find the answer, you need to solve ... | |
| Future Value & Compound Interest | 5/30/2010 |
| Q: Hello: I have a question regarding the compound interest and future value calculation at the ... A: After n terms at r percent, the amount is P((1+r)^n-1)/r). So after 1 year, with the deposits at the ... | |
| math | 5/29/2010 |
| Q: I wonder if you could help me with a problem associated with my pastime of geocaching. If you ... A: If a square is made with the length of each side as 1, then a side X is added to the top and bottom ... | |
| Statistics | 5/25/2010 |
| Q: It has been a while since I've dusted off my stats book. Can you clarify if a chi-squared test would ... A: Yes, it is the appropriate statistics to use. To do so, construct a table. In it, put two columns - ... | |
| arithmetic sequence | 5/24/2010 |
| Q: write the first five terms of the arithmetric sequence a1= 2 and a12=46. Thank you for your help! A: If we are given a12 and a1, then b=(a12-a1)/11 is the amount of space between each element. The ... | |
| Algebra | 5/24/2010 |
| Q: How do you know if a quadratic equation will have one, two, or no solutions? How do you find a ... A: For the quadratic equation ax² + bx + c, the solutions are given by x = (-b ± √(b²-4ac))/2a. ... | |
| Probability | 5/23/2010 |
| Q: 1.The probability that a person shopping at a mall will spend at least Rs. 250/- is 0.6. Find the ... A: 1. The probabilitiy of one person spending that much is 0.6. The probability of 4 people doing it ... | |
| probability | 5/21/2010 |
| Q: a box contain 3 black balls and 3 white balls.someone blindly takes 3 balls from the box and ... A: Note that C(a,b) is "a choose b", and that is a!/(b!(a-b)!). Lets look at taking 3 balls out of the ... | |
| pre-cal | 5/21/2010 |
| Q: A ball is thrown with an initial velocity of 80 feet per second at an angle of 40° with the ... A: If the ball is thrown at 80 f/s at and angle of 40° with the horizontal, the vertical speed is ... | |
| Integral | 5/20/2010 |
| Q: From 0-1 what is the Integral of (1-x^2)^(1/2) A: Let √(1-x²) = sinA. Not that sin²A + cos²A = 1, so cos²A = 1 - sin²A = 1 - 1 + x² = x². so ... | |
| Discrete Math | 5/19/2010 |
| Q: Question # 1 (a) How many one-to-one functions are there from a set’X’ with four elements to a ... A: Question # 1 (a) There are 4 elements in X, each of which can have 5 choices in Y. This makes the ... | |
| Function Tables | 5/19/2010 |
| Q: My son is having trouble with a problem he got for extra credit. Can you help please?! He has to ... A: At first I noticed the numbers were all 3^n or 2*(3^n) since 3^0 = 1, 3^1 = 3, 3^2 = 9, and 3^3 = ... | |
| geometry Problem (ALGEBRA) | 5/18/2010 |
| Q: 1) Martin leaves 10 kilometers from school. If he rides his bike at 12 kph and leaves the school at ... A: 1) It is known that P = 2(W+L) and the L = 2W + 5. If the width is decreased by 3 and the length by ... | |
| problem solving math thermodynamics | 5/17/2010 |
| Q: which would require more heat, melting 500 g of 0 degree c ice or turning 500g of 100 degree c into ... A: It takes a whole lot more energy to boil water than to melt ice. It only takes 80 calories to melt ... | |
| probability | 5/16/2010 |
| Q: General Buck Twigidson is preparing to make his annual budget presentation to the U.S. senate and is ... A: Let's go with a chance of x for between 50 and 70 percent approved. This makes the chance of between ... | |
| Uniform Motion Problem (intermediate Algebra) | 5/16/2010 |
| Q: 1) Martin leaves 10 kilometers from school. If he rides his bike at 12 kph and leaves the school at ... A: 1) If there are 10 k and he travel as 12k/h, it will take 10/12 of an hour. Multiply by 60 to get ... | |
| finance | 5/15/2010 |
| Q: How are you at financial statements? I am an Axia student at University of Phoenix and need help. I ... A: I took an engineering course in finances, kept the finnces for an orginization one year. There are ... | |
| Math | 5/12/2010 |
| Q: Probably a really easy one... Im trying to figure out this whole End Behaviour busniess.... My ... A: If the power is even and the coefficient on the term is positive, the graph goes up at both ends. If ... | |
| Catch train | 5/9/2010 |
| Q: I would like to solve on my own. I only need help on how to set up the equation. Trains A and B are ... A: Since A is at 80 mph and B is aat 96 mph, that means train B is travelling 16 mph faster that A. ... | |
| Sphere | 5/9/2010 |
| Q: a sphere of cast iron weighing 10kg.how is its diameter? A: The volume of a sphere is (4*pi*r^3)/3. The density of iron is 7.87 g/cm^3. If we have 10 kg of ... | |
| conversion problem | 5/8/2010 |
| Q: I have a conversion problem I need help with. figures of comparable avg. golf swing speed. over a 10 ... A: To get the horizontal speed, take the distance / time. This will give you the speed in cm / sec. ... | |
| Trigonometry | 5/7/2010 |
| Q: Name the quadrant or axis on which the terminal side of an angle standard position with the ... A: It is known that -125° is the same if you add 360° to it, so -125° + 360° = 235°. Now the each ... | |
| how to solve this equation | 5/6/2010 |
| Q: The Equation is T = L * exp(-2*L) The value of T is 0.0098 for L= 0.01 Then the book says that ... A: Make this into a function f(L) = log(2) - 2*L - log(0.0098). We are trying to find where this is 0. ... | |
| Trig. | 5/3/2010 |
| Q: Find tan (s + t) given that sin s = 1/4, with s in quadrant 2, and sin t = -1/2, with t in quadrant ... A: Since sin s = 1/4, s = 180° - arcsin(1/4). Since sin t = -1/2, t = arcsin(-1/2), where t is between ... | |
| verifying identities | 5/3/2010 |
| Q: tan x csc x cos x=1 A: For me, trig problems are looked at, and then changed to sin x and cos x if the solution is not ... | |
| Help with explainarion and write the equation | 5/2/2010 |
| Q: ""a party of hunters made a trip of 720 kilometers to a hunting lodge in 9 hours. they traveled 6 ... A: They travelled 720 km. They travelled for 9 hours. They travelled 6 hours on a paved road, which ... | |
| maths | 4/30/2010 |
| Q: Sir, pls hepl me with this question. It is for my son. Thanks a lot for your help in advance. 1) ... A: If she got 1023 bags of 7 mangoes, then that is 7*1023 = 7161 magoes in bags. a) If she had 4 left ... | |
| Trigonometry | 4/30/2010 |
| Q: 1.Verify: 1+sec theta= 1+cosine theta/cosine theta A: It is known that if we start with 1+secΘ = (1+cosΘ)/cosΘ, we can make one side into ... | |
| Math | 4/26/2010 |
| Q: I could not figure out the answer to this question. Write the four fourth roots of 81cis180 in ... A: To find the nth root of x*cisΘ, it is the nth root of x times cis((360°k+Θ)/n) where k = ... | |
| Trigonometric Identities | 4/24/2010 |
| Q: If T(n) = (sin x)^n + (cos x)^n , prove that 1. (T(3) - T(5))/T(1) = (T(5) - T(7))/T(3) 2. 2T(6) - ... A: I've answered [1] and [2] already, and now for [3]. If we take A = sin²x, the cos²x = 1-A. Note ... | |
| Plane Trigonometry: Fundamental Identities | 4/23/2010 |
| Q: I am to reduce the following function to single trigonometric function: (1 + sec x) / (tan x + sin ... A: I convert all trig functions to sin x and cos x unless another approach looks obvious. Now sec x = 1 ... | |
| combinations | 4/23/2010 |
| Q: why does 7C5=7C2 as well as 5C3=5C2 8Cx=8C(8-x)? A: This is because aCb = a!/(b!(a-b)!). For 7, if b=5, and a-b=2; this means if b=2, a-b=5. THe same ... | |
| Discrete Math | 4/22/2010 |
| Q: Given the partition {a, b, c} and {d, e} of the set S= {a, b, c, d, e}, list the ordered pairs in ... A: I'm not sure I get this, but I believe that we have two partions of S. Let them be A and B. A = {a, ... | |
| math analysis | 4/22/2010 |
| Q: amplitude 15, period pie over 6, point (1,0) find amplitude period,phase shift ,and vertical ... A: The amplitude is given as 15 and the period π/6. It does't give a max or min value for y, so ... | |
| Puzzle | 4/21/2010 |
| Q: if 76=131=12,91=108=2,53=82=6,96=153=12 then 72=?=? A: So, we have 76 => 131 => 12, 91 => 108 => 2, nd 96 => 153 => 12. Thus, we would have 11 => 21 => 1, ... | |
| Compount Interest Formula | 4/21/2010 |
| Q: Let's say that an investor has $1000.00 to invest for 3 years at a rate of 5% at compound interest. ... A: Well, (1+i)³ = 1 + 3i + 3i² + i³. If i is small, this can be approximated by 1 + 3i since 3i² is ... | |
| Discrete Math | 4/19/2010 |
| Q: Say 90 students go to a zoo. And we have the following data: • 21 have a hot dog, • 21 have a soda • ... A: There are three sets, A=hot dog, B=soda, and C=popsicle. The size of each is A, 21; B, 21; and C, ... | |
| Trigonometric Identities | 4/18/2010 |
| Q: If T(n) = (sin x)^n + (cos x)^n , prove that 1. (T(3) - T(5))/T(1) = (T(5) - T(7))/T(3) 2. 2T(6) - ... A: 1) T(3) = sin^3(x) + cos^3(x). T(5) = sin^5(x) + cos^5(x). That is the same as sin³x(1-cos²x) + ... | |
| Discrete Math | 4/18/2010 |
| Q: Say 90 students go to a zoo. And we have the following data: • 21 have a hot dog, • 21 have a soda • ... A: Let n be for intersection, u be for union, and _X be for not X. Let A be the number who had a hot ... | |
| Discrete Math | 4/17/2010 |
| Q: Given two sets R and S. Show that the union of the power sets of R and S is a subset of the power ... A: You can find the definition of a power set in http://en.wikipedia.org/wiki/Power_set If any set is ... | |
| angle of elevation | 4/17/2010 |
| Q: I've attached the question as a image. Can you help calculate this as I am really confused by this? A: From the picture, let x = BC and y = CD. It is known that tan16° = y/(30+x) and tan21° = y/x. Let A ... | |
| Discrete Structures | 4/16/2010 |
| Q: Recall that the Fibonacci sequence is defined recursively by F(1) = 1, F(2) = 1, F(n) = F(n − ... A: If is known that F(n+6) = F(n+5) + F(n+4). It is known the F(n+5) = F(n+4) + F(n+3), so F(n+6) = ... | |
| Discrete Structures | 4/14/2010 |
| Q: Given the set of of all binary strings of length 8, how many of these contain two or more zeros? A: Since they are binary, that is 2 choices per element. Since there are 8 elements, that is 2^8 = 256 ... | |
| Math | 4/14/2010 |
| Q: x+4[6-4(5x+8)]=67 A: This one was easier to do that to check. Take x+4[6-4(5x+8)]=67. Answer ------------------- ... | |
| 8 Planets in 12 Signs | 4/11/2010 |
| Q: Can you explain with proper formula that how to count maximum possibilities of 8 different planets' ... A: From what I understand of what you said ... There are 12 different signs. There are 3 signf for ... | |
| algebra | 4/10/2010 |
| Q: plz tell about algebra that what is algebra and where are use it and what purpose it from begining A: Algebra is used in many places. It starts with lines of the forms y = mx + b, where m and b are ... | |
| Linear Regression | 4/9/2010 |
| Q: How are problems of autocorrelation and multicollinearity identified in regression and how are they ... A: When regression is done, a constant times each variable is found that gives a fairly good fit. I'm ... | |
| math | 4/9/2010 |
| Q: Solve the following equation for the variable x: 2ax/4b + 3c/2d - x=1 A: Take 2ax/4b + 3c/2d - x = 1 and keep only those terms with an x on the left. In other words, ... | |
| Discrete Structures | 4/8/2010 |
| Q: How many different binary operations can be defined on a set with n elements? A: If one element is selected, there are n ways to do it. If the other element is selected, there are ... | |
| math | 4/8/2010 |
| Q: Simplify the following expression into a single fraction. Show your results in the lowest terms. ... A: First they need to each be reduced. The 1st can have the numerator and denominator divided by 3, ... | |
| Discrete Math | 4/7/2010 |
| Q: A computerized dating service has a list of 50 men and 50 women. Names are selected at random; how ... A: There could be (with a very small chance), if 50 are drawn, that all 50 aare of the same sex. To ... | |
| Discrete Structures | 4/7/2010 |
| Q: 11. You are developing new bath soap, and you hire a public opinion survey group to do some market ... A: In lathering, for instance, the average is 397/450, which is roughly 88%. The binomial distribution ... | |
| exponential equations | 4/5/2010 |
| Q: The coaches anger increased exponentially. Only 20 min after practice began, the coach was twice as ... A: If he gets twice as angry every 20 minutes, after forty that would be 2x2=4 times as angry. After ... | |
| Finance | 4/3/2010 |
| Q: Can you help me I know I am doing something wrong I just do not know where I am going wrong: ... A: The equation (1+.07)^4(1+x)^2=(1.075)^6 works out to 1.3107(1+X)^2=1.543302. Using this, we get ... | |
| abstract rate problem | 4/1/2010 |
| Q: I was given this problem and I can't find the right answer. Stacy observed that it took w women 10 ... A: This reduces down to w women doing j/10 jobs in a day. This further reduces to 1 woman doing j/(10w) ... | |
| Value of pi and e | 3/30/2010 |
| Q: Sir Scott, How can one derive the value of (or) find the limits equation for pi and e. Further how ... A: The number e is defined to be the number such that the derivative of e^x is e^x. The derivatie of ... | |
| Parametric Equations and polar coordinates | 3/30/2010 |
| Q: Eliminate the parameter and write the corresponding rectangular equation whose graph represents the ... A: Note that x = e^(2t) = (e^t)(e^t), so x = y*y = y². Thus, it can be said the y = ±√x. Given r ... | |
| Sequences and Series | 3/29/2010 |
| Q: Find the first 4 terms and the 8th term of the recursively defined sequences: 3. a1= 8 ; an = an-1 ... A: 3. Given that the next an is a_n -4, it canbe said that a_0 = 12 and a_n = 12 - 4n. Thus, a_1= 8, ... | |
| Precalculus | 3/26/2010 |
| Q: I need to find the exact value of the trigonometric function of cos(v-u), given that sin u=5/13 and ... A: This means the far leg with u angle is 5, so the near one is -12, since 5² + (-12)² = 13². So if ... | |
| trigonmetey | 3/24/2010 |
| Q: A woman at a point A on the shore of a circular lake with a radius of 3km wants to arrive at the ... A: Lets say she rows the boat first and the angle between the direction she rows and the direction she ... | |
| Coefficient of Variation | 3/23/2010 |
| Q: I'm looking into the coefficient of variation and as I understand it it is the Standard Deviation ... A: The variation between samples is done by the (sd)/m, where sd = stadard deviation and m = mean. If ... | |
| coordinates | 3/18/2010 |
| Q: Sir, can you exlain this question to me. What is the distance between the points with coordinates ... A: If you are given two points on a plane, say (1,5) and (9,-1), the distance is found by ... | |
| Polar Form | 3/17/2010 |
| Q: How would you express 5-2i in polar form, rounding to the nearest 10th? A: The real value is treated as x and the imaginary value is treated as y. This means the value 5-2i ... | |
| Area of a ring | 3/16/2010 |
| Q: Scott, How do I calculate the area of a ring with a triangular cross section (base .5", Height 1") ... A: It sounds like you're talking about swinging a triangle around in a ring. The outside of the ring ... | |
| math answer | 3/14/2010 |
| Q: 8x+4=3x+39?x A: I assume this is 8x + 4 = 3x + 39 and the question is, "What is x?" Take 8x + 4 = 3x + 39 and ... | |
| Type 2 error questions | 3/12/2010 |
| Q: 1) "The diameter of a wire should be 8 cm. It follows a normal distribution and has a standard ... A: 1a) The chance of a type I error is P(z>µ+kφ). In this case, µ = 8 and σ = ... | |
| advance algebra | 3/10/2010 |
| Q: a trapezoidal gutter is made from strip of metal 22 m wide by bending up the sides. if the base is ... A: If the metal is 22m wide and only 14m is left on the base, that puts 22 - 14 = 8 m on the sides. ... | |
| operation research | 3/9/2010 |
| Q: please give the answers for following 1)Find out the optimal solution of the following LP problem ... A: To solve LP (linear programming) problems, use a simplex tableau. That is, take the constants of ... | |
| Exponentials | 3/9/2010 |
| Q: I need help with some problems. I think I got the first one right but I do not know how to do the ... A: Note that 2^5 = 2*2*2*2*2 = 32 and 2^3 = 2*2*2 = 8. Since 32/8 = 4, that is 2^2. This means that ... | |
| Exponentials | 3/7/2010 |
| Q: I need help with some problems. I think I got the first one right but I do not know how to do the ... A: If it is e^((6x)/(7x)), then the x in the numerator and denominator of the fraction cancel. The ... | |
| Maths | 3/7/2010 |
| Q: I have 2 doubts. Pls clarify. Thanks a lot in advance. 1) Book X cost $8 more than Book Y.Book Z ... A: We are given x = y + 8, so y = x - 8. We are also given z = 3x. The other information say x + y + z ... | |
| Newton's Law of Cooling | 3/6/2010 |
| Q: A pan of warm water (46 degrees Celsius) was put into a refrigerator. Ten minutes later, the water's ... A: The equation is T(t) = (To)(e^(at)) fpr some constants To and a. The value is given that when t=10, ... | |
| algorithm for polynomial simplification | 3/5/2010 |
| Q: Greetings sir, I know this is not likely,but does there exist a linear algorithm(or is one possible) ... A: No. Not all polynomials are factorable. Examle: x² + x + 7. Using calculus, if f(x) = x² + x + 7, ... | |
| plz solve these problem as early as possible. | 3/5/2010 |
| Q: 1) Find out the optimal solution of the following LP problem through SIMPLEX method. Maximize Z = ... A: 1) Solved in attachment. The variable to be added is in bold at the top, the possible values are on ... | |
| Logarithmic and Function Domain | 3/4/2010 |
| Q: I need help with some problems. I think I got the first one right but I do not know how to do the ... A: e^6x/^7x - is it e^((6x)/(7x)) = 1? Then you do get (6x)/(7x), which reduces to 6/7. ... | |
| Solve θ | 3/3/2010 |
| Q: 2tan²θ + secθ - 4 = 0, 0º ≤ θ ≤ 360º A: I convert all trig functions to sin and cos. It is known that tan=sin/cos and sec=1/cos, so the ... | |
| Grade 9 Math | 3/2/2010 |
| Q: I have attached a scanned copy of the question. Please assist me in solving this equation as I am ... A: 1. The volume of a cyllinder is the base * height, so with radius r and height h. The area of the ... | |
| distance=s x time | 3/1/2010 |
| Q: 40x = 60(x+1) can you please explain this and solve it :) thank you A: Multiply out the equation on the right side, giving 40x = 60x + 60. Subtract 60x from both sides, ... | |
| math | 3/1/2010 |
| Q: please help me solve this problem using the addition method of solving equations with 3 variables. ... A: This problem doesn't have real simple solutions. They are -34/87, 2/87, and 37/87. In the first ... | |
| Pre-Calc | 2/28/2010 |
| Q: Find the work done lifting a 100 pound bag of potatoes 3 feet. *Use vectors A: The units of work are in fot-pounds. The weight would be 100 pounds, so draw a circle on the bottom ... | |
| math | 2/27/2010 |
| Q: You are dealt one card from a 52 card deck,what is the probability of being dealt a card greater ... A: Note that the number would be 4, 5, or 6. Since there are 3 numbers, and there are 4 choices for ... | |
| answers to aptitude questuons | 2/27/2010 |
| Q: There are two concentric circles. The radius of the outer circle is 8.5 cm and the length of the ... A: Bigger radius is R = 8.5. A tangent line to the smaller that touches the outer at both ends has ... | |
| Pre-calc | 2/26/2010 |
| Q: Find csc(arctan 8/15) Thank you A: If an angle as a tan() of 8/15, the far side could be 8 and then the near side would be 15. Thus, ... | |
| Pre-Calc | 2/26/2010 |
| Q: sin(-5pi/4) A: When 2π is added, it makes no difference, for the sin() wave repeats every 2π. Since ... | |
| Probability question....sorta | 2/25/2010 |
| Q: Mr. Wilson, I've read (in several sources) that it only takes 23 people in the same room before the ... A: We need to check every pair of people in the room. Given only 2 peoole, say A and B, there is only 1 ... | |
| Calculus 2 | 2/24/2010 |
| Q: the intergral of 1/(2x^3+x^2-x) dx , i get stuck after simplifying it to 1/[x(2x-1)(x+1)] can you ... A: This is referred to as integration by parts. Set 1/(2x³+x²-x) = A/x + B/(2x-1) + C/(x+1). To find ... | |
| Pre cal | 2/22/2010 |
| Q: How do you find the exact value of sin 5pie over 12 by using the half-angle formula? A: Note: pie is good to eat, but π is a greek letter and is spelled pi. Use the 1/2 angle ... | |
| Game Theory | 2/21/2010 |
| Q: Find the solution of the following game. Cosby A B C A 3 -3 -6 Ronny ... A: There are different approaches in game theory. There is the min-max, the max-min, and the best ... | |
| A tricky little David Hasselhoff problem... | 2/21/2010 |
| Q: I'm looking for a method and general solution to the following problem. David Hasselhoff is ... A: There is some point k that is on the x line with David being at being 0. The distance k is where he ... | |
| 3 variable linear eqaution | 2/19/2010 |
| Q: x+2y-4z=2 -x+2y-4z= -2 -xx-2y+4z= -2 A: I assume that two x's were accidentally typed in the 3rd equation. Normally, 3 equations and 3 ... | |
| Prove that: | 2/15/2010 |
| Q: Can you please help me prove the following: 1/cosec (theta) - 1 + 1/cosec (theta) + 1 = 2 tan ... A: The problem is 1/(cscθ - 1) + 1/(cscθ + 1) = 2•tanθ•secθ. Multiply the 1st ... | |
| Prove that: | 2/15/2010 |
| Q: Can you please help me to prove the following: 1/cosec Θ - 1 + 1/cosec Θ + 1 = 2 tan ... A: I write cosecθ is written as cscθ. The formula needs parenthesis in it and is ... | |
| Projectile motion | 2/13/2010 |
| Q: A diver leaves a 3m board on a trajectory that takes her 2.5m above the board and then into the ... A: To solve this problem, do the following: 1) find the time for 2.5 meters up, given she was at rest ... | |
| algebra | 2/11/2010 |
| Q: Given A=P(1+0.01R)to the power of n. find the value of n if A=575,P=90 and R=0.17 I am not able to ... A: Put in the values given. That is, 575 = 90(1 +0.0017)^n. Divide both sides by 90, so it becomes ... | |
| Maths - Coordinate Geometry | 2/10/2010 |
| Q: This problem simply dazzles me: The straight line with equation y = kx is a tangent to the circle ... A: By the way, sin(x)/cos(x) = tan(x). Yet now I see how to do it without sin() and cos(). We know ... | |
| Maths - Coordinate Geometry | 2/10/2010 |
| Q: This problem simply dazzles me: The straight line with equation y = kx is a tangent to the circle ... A: Draw a right trianlge with one end at the origin, the other a the circle center, and the other ... | |
| stats | 2/6/2010 |
| Q: given P(A)=.4 p(B)=.3 P(A|B)=.3 and B'=B(compliment)how would I calculate P(A intersect B')? I ... A: Note that P(AnB)/P(B) = P(A|B). We are given P(B) = 0.3 and P(A|B) = 0.3. This means P(AnB)/0.3 = ... | |
| Math: Function Table | 2/5/2010 |
| Q: I need help finding the rule for this question. x: 1/2, 1/3, 1/4, n, 1/6 y: 1/3, m, 1/6, 2/15, 1/9 ... A: On fractions, when one fraction is divided by another, invert the bottom fraction and multiply by ... | |
| math | 2/4/2010 |
| Q: solve by applying the quadratic formula; all radicals should be simlified as far as possible. show ... A: The quadratic equation is x = (-b±√(b²-4ac))/(2a). Here, a=1, b=-12, and c=35. From here, ... | |
| integration | 2/4/2010 |
| Q: how do i integrate (3e^(3x+y))dx? does it just equal e^(3x+y) or does the y effect the solution? A: It is known that ∫e^x dx = e^x + C. If f(x) = e^(ax), then f'(x) = ae^(ax). Thus, ... | |
| precalculus | 2/3/2010 |
| Q: switch to polar coordinates y= 3x^2 + 1 A: It is known that x = r*cosA and y = r*sinA, so put theses in. The result is r*sinA = 3r²cos²A + 1. ... | |
| Probability | 1/27/2010 |
| Q: What is the probability that among n people in a room at least 2 have the same birthday? A: Now when there are 3 people, Angelo, Mona, and Lisa, one may be a painter, but that's another story. ... | |
| hi | 1/27/2010 |
| Q: 1.the sum of the first 5 terms of an arithmetic series is 35 and the sum of the next 5 terms is 160. ... A: Now to define the arithmetic series I will refer to, assume that it is a, a+n, a+2n, a+3n, .... 1. ... | |
| Vectors | 1/26/2010 |
| Q: i answered this question. but not sure if it is right. the question is: A boat crosses a river and ... A: This of his speed as the hypoteneuse of a triangle and the current as the side going downstream. We ... | |
| Water Level vs Surface area | 1/26/2010 |
| Q: Lake Mead is an artificial lake formed by the hoover dam, covering parts of both Arizona and Nevada. ... A: Assuming the banks are pretty close to vertical, that wold be 16.8 m * 640 km². Now the answer is ... | |
| Turning an equation into standard form for a circle and finding the radius and the center. | 1/25/2010 |
| Q: I was wondering if you could help me out. I am trying to help my little brother with his math ... A: The standard form of a circle is (x-a)² + (y-b)² = c² where (a,b) is the center and c is the radius. ... | |
| Probability | 1/24/2010 |
| Q: A box of 20 items is inspected by checking a sample of 5 items.If none has a defect then the box is ... A: Take C(a,b) as "a choose b". That means C(5,2) = "5 choose 2" = 5!/(2!(5-2))! = 5*4*3*2*1/(2 * ... | |
| Probability | 1/23/2010 |
| Q: Three fair dice are tossed: a)What is the value set for the random variable that sums the value on ... A: a) The values of 3 six sided dice would each be 1, 2, 3, 4, 5, or 6. b) The value of the sum is a ... | |
| capacity of a cylinder | 1/22/2010 |
| Q: A cylindrical tank with a 4ft-3in diameter holds 600 Us gallons of water, what is it's height? The ... A: There are 231 in³ in a gallon. This means that 600 gallons is V = 138,600 in³. If the diameter of ... | |
| Probability | 1/21/2010 |
| Q: Question I have a bag of 30 balls 5 are red 6 are blue 19 are black If I randomly select balls ... A: Number of ways ---------------------------- The number of ways of getting 5 red out of the 5 red in ... | |
| Probability | 1/20/2010 |
| Q: Question I have a bag of 30 balls 5 are red 6 are blue 19 are black If I randomly select balls ... A: Let C(a,b) = a!/[b!(a-b)!]. Note that C(c,0) = C(c,c) = 1. Also note that C(c,1) = C(c,c-1) = c. ... | |
| RE: | 1/20/2010 |
| Q: .. I came across on of these problems in profit,loss and discount:- A DEALER SELLS 2 ARTICLES AT ... A: Lets suppose the item cost $90. A 10% profit would mean he sold it at a price so that the 10% ... | |
| math | 1/19/2010 |
| Q: state the domian of [f of g](x) for f(x)= squared root of x-16 and g(x)=5-x A: The domain and range of g(x) is all x since g(x) is a line. However, the domain and range of f(x) ... | |
| Quadratic Formula | 1/16/2010 |
| Q: I was told this one's pretty simple but I just can't seem to figure it out, here it is: If a ... A: Basically, the height over the safeway net is 60 - 16t². I will call this h(t) = 60 - 16t². To find ... | |
| Advanced algerbra | 1/15/2010 |
| Q: {3x+2y=-3 {2x-5y=17 A: Multiply the 1st equation by 2 and the second by -3. Ad them together and all that is left is 4y+15y ... | |
| Advanced functions | 1/12/2010 |
| Q: How do you find the instantaneous rate of a substancw whose half life is reached for the equation : ... A: To find the instantaneous rate of change, take the derivative. This said, P'(t) is the same ... | |
| geometry and trigonometry | 1/10/2010 |
| Q: Let a and b be the straight lines with equations y=m1x+c1 and y=m2x+c2 where m1*m2 notequal to 0. ... A: It can be shown the new x and new y are gotten by the formulas xcosΘ + ysinΘ and ... | |
| Sequence question | 1/8/2010 |
| Q: I really appreciate it. a) determine the value of x such that x+2, 2x+3, 4x-3 are consecutive ... A: I put this data in Excel with x+2 as T1, 2x+3 as T2, and 4x-3 as T3, then made D1 = T2 - T1 and D2 = ... | |
| Math (combinatorics question) | 1/7/2010 |
| Q: If you want to get a set of 5 different pictures out of set of 90 pictures, how many distinct sets ... A: The number A choose B, usually A over B with parenthesis around the outside, is known to be ... | |
| Antiderivatives | 1/7/2010 |
| Q: What is the antiderivative of the function f(x) = (2+x^2)/(1+x^2)? Thanks. A: Here are a few things that need to be known which are discussed below. 1) The antiderivative is the ... | |
| Rolling One Dice Twice - Probability | 1/5/2010 |
| Q: Here we are on a snowy evening in the UK playing Yahtzee. Please can you explain the probability ... A: The probability function for one die is # p 1 1/6 2 1/6 3 1/6 4 1/6 5 1/6 6 ... | |
| math | 12/23/2009 |
| Q: Hey Scott Question 1 A rectangular garden measure 4m by 4m.Its area us to be tripled by extending ... A: 1) To triple a garden, that means its length and width need to me multiplied by √3. To find ... | |
| Quantitative Analysis | 12/20/2009 |
| Q: This is the situation: After negotiarions with the financial department of Magrite Inc., and the ... A: A) Solve 3.1x + 2500 = 7.50x. B) Solve 9x = 3.1x + 2500. C) The break even point represents the ... | |
| Algorithm to Divide up a Pie | 12/17/2009 |
| Q: Could you tell me what is the algorithm to divide up a pie between 2, 3, 4, ... N number of people ... A: I'm not sure if this was suppose to be answered, but I've got to answer everything I get. Now I ... | |
| using fundamental identities | 12/16/2009 |
| Q: use the given values to evaluate(if possible) all six trigonometric functions. tansquare root ... A: This will draw a triangle in Qadrant III that has a hypoteneuse of 2 and a far side of 1, so the ... | |
| Finete Math | 12/15/2009 |
| Q: For the following problems, determine how many years it will take for the two accounts to reach the ... A: The 1st one is 1000(1 + 0.03/12)^(12t) = 1100(1.0302)^t. To solve, note that 1000/1100 = ... | |
| complicated shoelace method | 12/15/2009 |
| Q: The triangle ABC has vertices A(2,6), B(-10, 1) and a third vertex C whih is on the line 5x-2y=18. ... A: The distance from A to B is √((2--10)²+(6-1)²) = √(12²+5²) = √(144+25) = ... | |
| Graph of a function | 12/14/2009 |
| Q: Describe the end behavior of the graph of the function y= -3x^4+3x^2-2 A: It is similar to a downward facing parabola, only more intense. Just a moment - let me do it in ... | |
| Differential Equations | 12/8/2009 |
| Q: initial value problem y'(t)+(1\t)y(t) = e^t, y(1)=2 A: Multiply the entire equation by t. This gives ty' + y = t(e^t). If we take yt, it can be seen that ... | |
| trig and prob | 12/3/2009 |
| Q: i couldn't get the write answer. a penalty shoot-out in a game of hockey requires each of 2 players ... A: 1) This means that the 2nd player scored and the 1st didn't. Since the 1st player has a probability ... | |
| solving system of equations in three variables | 12/2/2009 |
| Q: 2x-y+2z=15 -x+y+z=3 3x-y+2z=18 A: I have the data in a table. The equations are up at top. The numbers are put in the first matrix. ... | |
| probability | 11/30/2009 |
| Q: hey :)!ok two cubical dice are thrown,one red and one blue. the scores on their faces are added ... A: I am confident that the answer I gave you is correct. I reviewed it several times, and am sure of ... | |
| Equation of lines | 11/30/2009 |
| Q: From your research, you determine that the price is $20 per a shirt, your company will be willing to ... A: Equation to use: y-y1 = (y2-y1)(x-x1)/(x2-x1), so y = y1 + (y2-y1)(x-x1)/(x2-x1). Company x1=26, ... | |
| Probability, continuous | 11/29/2009 |
| Q: f(x)= 0.....................x < -1 (0.75 - 0.75x^2)......-1 ≤ x ≤ 1 ... A: I know the mean was calculated correctly and believe the variance is the E(x²). It looks like the ... | |
| Calculus | 11/28/2009 |
| Q: I am studying for a calculus exam and I would like to get some advice on how to address each of the ... A: (i) The domain of the function is whatever x values can be put in. Since the denominator involves an ... | |
| Probability & Statistics | 11/26/2009 |
| Q: A company manufactures widgits, if there is a 3% chance a widgit is useless how many widgits should ... A: Using the normal approximation to the binomial with n=100, p=0.03, and 1-p=0.97, it is known that ... | |
| math | 11/26/2009 |
| Q: I'm sorry there is a typing error in my previous sum ... A: So if the 1st angle is 30° and the second angle is 42°, and the difference in the base is 60, the ... | |
| integral | 11/25/2009 |
| Q: I am having a problem with finding the length of the curve. y=x^(2/3)between x=-1 and x=8. I know ... A: This took quite a bit of work and I managed to get it wrong for half a dozen pages, but I think I ... | |
| trigonometry | 11/23/2009 |
| Q: Tan^2x/Sin^2x=1+Tan^2x and Sin^2x/1-cosx=1+cosx A: It is known that tanx = sinx/cosx, so tan²x = sin²x/cos²x. When tan²x is divided by sin²x, the only ... | |
| mathematics | 11/20/2009 |
| Q: 1. Intergrate with respect to x :(x^2-3) 2. The linear speed of a belt that passes round a pulley of ... A: 1. ∫(x^2-3)dx The answer would be to add one to the exponent and divide by new exponent. That ... | |
| Trig | 11/17/2009 |
| Q: Good evening, my questions are these: 1. How would I verify the identity of; ... A: 1. Use sin5x = sin(4x+x) = sin4x•cosx + sinx•cos4x, sin3x = sin(4x-x) = sin4x•cosx - sinx•cos4x, ... | |
| Easy Counting Problem? | 11/16/2009 |
| Q: Consider the following variables: Z A1 ... A: The counting looked good, and, well, I looked over it, and the only eror I think I saw was when the ... | |
| Pre-calculus | 11/10/2009 |
| Q: I need help... I don't understand how to do this problem using the rational zeros thereom to find ... A: To simplify things, note that every factor is divisible by 3. Thus, 3x^3+6x^2-15x-30 = 3(x³ + 2x² - ... | |
| trig | 11/9/2009 |
| Q: Directions- solve each equation for solutions over the interval [0*,360*] (*=degrees). Give ... A: There is a trig identity involved here. Note that cos(2Θ) = cos²Θ - sin²Θ. So when ... | |
| Pre-Calculus | 11/8/2009 |
| Q: Scott, I need help with this problem. State an equation whose graph is a transformation of the sine ... A: The variable is x and the function is sin(x). The amplitude is the value that occurs before the ... | |
| Chaotic Systems?? | 11/7/2009 |
| Q: I was wandering if you could answer myWhat kind of mathematics am I dealing with here? Consider ... A: That would be a miatrix of almost infinite size with variables for each action somewhere between 0 ... | |
| Statistics, probabilities | 11/6/2009 |
| Q: There were some other part-questions that I've solved, but I don't know about these, I hope I could ... A: a) The chance of H is 0.4 and T is 0.6. This is two choices the same for three times. That is the ... | |
| Indefinte Integrals | 11/6/2009 |
| Q: I have these problems and have been struggling with them. Can you help?? Thanks! A: ∫x^n dx = x^(n+1)/(n+1) + C, ∫sinx dx = -cosx + C; ∫cox dx = sinx + C, ∫e^x ... | |
| algebra 2 | 11/4/2009 |
| Q: okay, here's my problem: if a-(1/a)=6, find a^2+1/(a^2) and a^3-1/(1^3) I was able to figure out ... A: If a - 1/a = 6, then multiply the entire equation by a. This gives a² - 1 = 6a, or a² - 1 - 6a = 0, ... | |
| math | 11/4/2009 |
| Q: solve these three equations 9a+7b=-30 8b+5c=11 -3a+10c=73 A: I put the answer in another file for you. The element that is in bold is what the row that it is on ... | |
| urgent math | 11/3/2009 |
| Q: Hey there I have a test tomorrow nigh for Calc and I just can't seem to get the answers for these ... A: 1a) Make one side of a right triangle as the rest of the way to first d. Make the other side the ... | |
| trig | 11/3/2009 |
| Q: You are standing 50 meters from the base of a tree that is leaning 4° from the vertical away from ... A: // a program to find the height of a tree #include <stdio.h> #include <math.h> void main() { ... | |
| Simplifying with Pascal's Triangle | 11/2/2009 |
| Q: Can you please help me simplify these products using Pascal's Triangle? (x+1)^5 (x+1)^6 (x+1)^7 ... A: Pascal's Triangle: Each row is found by the sum of two elements above it. On the edge, it is always ... | |
| maths-probability | 11/1/2009 |
| Q: A six digit number (abcdef)each digit can vary from 0to9. A number is said to be a lucky number if ... A: Take a foud sided die. Flip it once, it would be 1: 1 2: 1 3: 1 and 4: 1. If you flipped it again, ... | |
| MATLAB | 11/1/2009 |
| Q: Could you help me create a MATLAB program that reduces ANY 5x5 matrix to its reduced row echelon ... A: I've never programmed in MATLAB, but after a few questions, I should learn. I like to space two ... | |
| Two Matrix questions | 10/31/2009 |
| Q: A = (a 3) (1 a+2) a) Find the inverse of the matrix for the a-values which there is an ... A: a) If the determinant of a matrix is non-zero, there is an inverse. The determinant of that matrix ... | |
| Algebra | 10/31/2009 |
| Q: How many prime factors does the binomial y4096 – 1 have? How do I show the work? I am very lost at ... A: That number 4096 = 2*2*2*2 *2*2*2*2 *2*2*2*2 *2*2*2*2 You know, multiply 2 by itself 12 times. ... | |
| Quadratic Equation | 10/30/2009 |
| Q: I have linear graph, real simple, "Y=X" I need to scale down my highest number '23' by multiplying ... A: You mean Y = 0.53X? Multiplying the first column by 0.53 gives the second column. 23 12.19 22 11.66 ... | |
| ap calculus ab | 10/30/2009 |
| Q: My Problems (set 2): [DN1] Find the slope of y=3x² at the point (-2, 12). [DN2] How many vertical ... A: [DN1] The slope is the first derivative. If f(x) = 3x², f'(x) = 6x. If we take (x,y) as (2,-12), ... | |
| intermediat algebra | 10/29/2009 |
| Q: what is the greatest common factor of these monomials, 50s^5t^2, 6s^3t^4, and 12s^4t^4 A: Look at the individually as a number, s, and t. Of 50, 6, and 12, we know that 50=2*5*5, 6=2*3, and ... | |
| Trig | 10/27/2009 |
| Q: I need help with this problem, please: (16 pts) The Pentagon in Washington D.C. is 921 feet long on ... A: Let C be the center and D be the far side. By extending DC through AB, AB will be split in half. ... | |
| how many | 10/26/2009 |
| Q: this is for my own personal curiosity how many grains of sand would fit into a 1 inch cube box ... A: I found it at http://wiki.answers.com/Q/How_many_grains_of_sand_are_in_one_square_inch In here, it ... | |
| largest number | 10/26/2009 |
| Q: i,v heard of groups of large numbers - e.g. million, trillion, zillion but what is the next ... A: I'll define a zillion at the bottom. 1,000 = one thousand 1,000,000 = one million 1,000,000,000 = ... | |
| The Law of Cosines | 10/25/2009 |
| Q: Scott - Can you, please, help me with this homework problem? Solve the triangle, if possible: B = ... A: It is known that b² = a² + c² - 2ac•sinB. Using B = 72.66˚, a = 23.78 km, c = 25.74 km, b can ... | |
| mathematical analysis | 10/24/2009 |
| Q: We have a question that we would like some help. Let A and B be subsets of R^d. Prove that ... A: Let S(A) be defined as the elements on the surface of A. Let S(B) be defined as the elements on the ... | |
| power and root | 10/24/2009 |
| Q: How do you solve the following questions: (1) what is the least possible value of a+b+C if a* ... A: 1st, find the prime factors of 3600. They are 2*2*2*2*3*3*5*5. We must choose three of them to be ... | |
| Trig Identities | 10/23/2009 |
| Q: I need help with this problem: Carefully prove the identity (cos x - sin x)^2 = 1 - sin 2x. Thank ... A: Start with the left, (cos x - sin x)². The works out to be cos²x - 2(sin x)(cos x) + sin²x. That ... | |
| inequalities | 10/22/2009 |
| Q: I am in 9th grade algebera 1. Having trouble with thisFind a value of "a" such that the number line ... A: If we are given that ax + 4 < 12, we can subtract 4 from both sides. The result of that is ax < 8. ... | |
| Probability | 10/21/2009 |
| Q: The marketing manager of a company has noted that she usually receives 10 complaint calls from ... A: I would use the poisson distribution. That would have poisson distributin with lamda = 10. I will ... | |
| Algebra | 10/20/2009 |
| Q: help me solve this equation 1/cubic root(x) +cubic root of x = 3 ... A: Let A = cube root(x). Our equation is then 1/A + A = 3. Multiplying by A gives us 1 + A² = 3A. ... | |
| trigonometry | 10/20/2009 |
| Q: log base2 x+log base2 4+log base2=32 A: I will assume that log in this note is log base 2, so as to make it look simpler. log(x) + log(4) + ... | |
| ap calculus ab | 10/18/2009 |
| Q: My problems (set5): 3. Consider the function (this is a piecewise function) g(x)=(x²+h), if x<(-1) ... A: 3) We are given g(x). It is x<-1: x²+h -1<x<1: x+4 1<x: x/(x+k) At x=-1, (-1)²+j = -1+4 => ... | |
| Fractions | 10/17/2009 |
| Q: 5% X $2000 = $100 2% X $1000 = $20 Can any of the fractions of 1/6 or 5/6 be determined from the ... A: Well, $100.00 + $20.00 = $120.00. If we look at $20/$120, we can cancel the $ and get 20/120. A 0 ... | |
| Fractions | 10/17/2009 |
| Q: 5% X $2000 = $100 2% X $1000 = $20 Can any of the fractions of 1/6 or 5/6 be determined from the ... A: I see it now. That is, 20/120 = 1/6 = 16 2/3% and 100/120 = 5/6 = 83 1/3%. I would divide it by 1 ... | |
| mathematical economic 201 | 10/16/2009 |
| Q: i am student of mathematical economic 201 i have few question i can not solve it can you help me to ... A: a) P = ((1+i)^-1)/i)A/(1+i)^n where A is the annuity value and i is the interest rate. b) If we are ... | |
| algebra - subspaces | 10/14/2009 |
| Q: let W be the set of all symmetric 3x3 matrices. Determine whether or not W is a subspace of the ... A: To be a proper subset, any scalar times and element must be in the subspace. Since A being in W ... | |
| Proving Trigo | 10/13/2009 |
| Q: tanA / (1 - cotA) + cotA / (1 - tanA) = 1 + secA cosec A A: The equation, converted to sinA and cosA is (SinA/CosA)/(1 - CosA/SinA) + (CosA/SinA)/(1 - ... | |
| Quantitative Analysis | 10/12/2009 |
| Q: Respected Sir, Please help me for below mentioned questions. Sir ! please provide me solutions. ... A: 1.From the following data compute quartile deviation and the coefficient of skewness: Size 4.5-7.5 ... | |
| linear equations | 10/12/2009 |
| Q: The manager of a fish store has water that is 10% salt and water that is 25% salt. He needs to fill ... A: a. If A is the 10% salt and B is the 25% salt, the equation is (0.1A + 0.25B)/(A+B) = 0.2. Also note ... | |
| Graphing an equation | 10/11/2009 |
| Q: .. just having trouble with this. Can't even make sense of my class notes. Can you tell me how to ... A: For everything on the right, move it to the left and combine terms. The result is -4x² + 5x² 6x - ... | |
| prime and composite numbers | 10/8/2009 |
| Q: I need to provide a theorem that requires the application of the definition for prime and composite ... A: A compostie number is defined to be the product of at least two primes. A prime number is defined to ... | |
| Solving a trig equation | 10/8/2009 |
| Q: I have been working on this problem for a day and I am utterly lost. ... A: It is known that sin(A+B) = sinA•cosB + sinB•cosA. First, we need to factor the √2 out front. ... | |
| eigenvalues andeignvectors | 10/7/2009 |
| Q: find all eigenvalues and eigenvectors of the matrix and find the matrix that diagoalises it 5 ... A: I have put the answer in a spreadsheet and exported the printed version to you. I'm not so sure ... | |
| Explanation of calculus application | 10/7/2009 |
| Q: Received the following during an Economics lecture. Its to explain elasticity. Could you please ... A: When k is used, it is in both K and k, but I will assume these are the same. When the elasticity of ... | |
| probability | 10/6/2009 |
| Q: I just can't work out the theory to get the right answer. The question is "Two cards are chosen at ... A: The chance has to be viewed as three possibilities. One: The five of diamonds is not drawn. Two: The ... | |
| formula?2 | 10/6/2009 |
| Q: "hello Mr. Wilson: i was referred to you by Ms. Wallin. I'm a bit fond of math formulas, so every ... A: If that is the case, put them in order. (x+4517)=63598516622171 (x+4646)=78961486137918 ... | |
| formula? | 10/5/2009 |
| Q: "hello Mr. Wilson: i was referred to you by Ms. Wallin. I'm a bit fond of math formulas, so every ... A: (x+4517)=63598516622171 (x+4557)=36495208111338 (x+4576)=97984080144061 (x+4586)=47257090258318 ... | |
| the completeness axiom | 10/5/2009 |
| Q: let Xn be and Zn be sequences of real numbers. suppose that lim as n tends to infinity is 0. suppose ... A: For any α small enough, show that (Zn)(Xn) < α. Since Zn is bound and lim x->∞ is ... | |
| ap calculus preparation | 10/4/2009 |
| Q: my problems (set 2): 2. Let g(x)= radical(x). Find: (a) g(5s+2) (b) g(radical(x)+2) (c) 3g(5x) (d) ... A: 2. Let g(x)= √x. To do these, put in what is in the parenthesis for x. (a) g(5s+2) ... | |
| Math logic problem | 10/2/2009 |
| Q: Can you tell me the formula that will provide the practically and intuitively meaningful results for ... A: Take the amount gained over the amount lost (make the amount lost positive). Also, you might want to ... | |
| Simultaneous Equations | 10/1/2009 |
| Q: A mans age is three times his sons age. Ten years ago he was five times older than his son. By ... A: Let M=man and S=son. The first equation we are given is M = 3S. Ten years ago refers to M-10 and ... | |
| math | 9/30/2009 |
| Q: Let a_n=(1/n).we claim that (a_n)_n=1(n goes to infinite) converges to 0.now for ε >0 let ... A: Let me rephrase it so it makes more sense. Let a_n = (1/n). We claim that if (a_n)•n = 1 for all ... | |
| Trig please help | 9/29/2009 |
| Q: The figure shows a circular piece of sheet metal of diameter 40 centimeters. The sheet contains 12 ... A: I will assume the bolt holes are around in a circle. Determin the distance from the center for each ... | |
| Math of covariance, correlation coefficient & Bond valuation | 9/28/2009 |
| Q: Please Sir, give me a solution of this financial mathmatics...Given the following historical data ... A: I'll use S for a sum. The variance is calculated as (S(x²) - S(x)²/n)/(n-1). This can be done for ... | |
| Factoring | 9/28/2009 |
| Q: How would I go about factoring x^5-c^5? A: It is known that x^n - 1 is (x+c)(x^n-1 - x^n-2 + x^n-3 ... - n - 1) with alternating +,- for n odd. ... | |
| mental arithmetic | 9/26/2009 |
| Q: What I am interested in is mental arithmetic.I really admire those people who can do sums in his ... A: This sounds interesting and tends to bring a lot back to my head, so buckle down and lets go. ... | |
| solving systems of linear equations in 3 variables | 9/25/2009 |
| Q: 2-y+z=5 -2x+2y+2z=-2 2x-3y-3z=1 A: Take the equations 2-y+z=5, -2x+2y+2z=-2, and 2x-3y-3z=1, and put them in proper form. That is, A) ... | |
| Math | 9/24/2009 |
| Q: Show that: y= 4x^2 (1-x^2) if sin^-1 y= 2cos^-1 x A: We need to show y = 4x²(1-x²) if arcsin(y) = 2arccos(x). If sinA = y, then cos(A/2)=x. This ... | |
| Fourier series | 9/23/2009 |
| Q: given function f(x)on (-L,L) If f(x) is even(cosine series) ,odd(sine series) ,either(Fourier ... A: I don't believe a function on the interval (a,b) is referred to as even or odd, but only when the ... | |
| Percentages | 9/22/2009 |
| Q: Here is an example in which an investor divided $30,000 into two accounts at simple interest: ... A: I will take A as the 5% investment, B as the 3% investment, and C as the 2% investment. 1) Change ... | |
| function rule | 9/22/2009 |
| Q: What is function rule of following table 2 7 3 10 6 13 9 19 n A: Set up the equations with the matrix a b d b c e where a = count, b = sum of x, c = sum of x², d = ... | |
| Graphing an Equation? | 9/21/2009 |
| Q: I need help with the STEPS (preferrably very detailed steps) on graphing the following equation (and ... A: The equation is x² - 7x - 8x - y² - 2y + 6y +20 + 21 - 2 = 2 - 4y - 2y² - 5x. Combining like terms: ... | |
| math | 9/16/2009 |
| Q: "David forgot to put three plus (+) signs and one minus (-) sign in the problem below. Can you help ... A: I'll have to think about that awhile. I won't be back until next Monday. I am currently busy doing ... | |
| College Algebra | 9/16/2009 |
| Q: One pipe can fill a tank three times as fast as another pipe. If together the two pipes can fill ... A: I assume that it is suppose to be q(x)= x^4+2x^3+8x^2+8x+16 (I believe the = should be a +). I ... | |
| Center and Radius of a Circle | 9/16/2009 |
| Q: Find the center and radius of the circle 2x²+2y²+6x-4y+6 A: The standard form is (x-x0)² + (y-y0)² = r² where (x0,y0) is the center and r is the radius. First, ... | |
| algebraic functions | 9/16/2009 |
| Q: My daughter was given a challenge problem and we have been stumped. The Input numbers are: ... A: Compare what is give to the output. The first thing to note is the differences. The input always ... | |
| Percentages | 9/15/2009 |
| Q: Here is an example in which an investor divided $30,000 into two accounts at simple interest: ... A: I don't usually take time to find mistakes, I just show how I do the problem. First case: $10,000 @ ... | |
| continuity | 9/15/2009 |
| Q: I am trying to use interval notation to tell where f(x)=5x+~4:(x) 5x + (superscript 4 square root ... A: That sound like the problem is computing the 4th root of x. Note the squareroots are the same as ... | |
| Pre-Cal | 9/13/2009 |
| Q: Fourth roots of 625i a) find the indicated roots of the complex number. b) represent each of the ... A: Questions will be answered at the end of this note. Read on to find out how to do it. Look at the ... | |
| show that it is orthogonal to both u and v | 9/13/2009 |
| Q: find u X v and show that it is orthogonal to both u and v. u= 6k v=-i + 3j + k Thank you! A: The vector u can be written as <0, 0, 6> and the vector v can be written as <-1, 3, 1>. The cross ... | |
| Percentages | 9/11/2009 |
| Q: $2.00, $4.00 and $6.00 are multiplied at three different percentages. The sum of the dollar amounts ... A: The total amount of money we have is $12 and the percentae desired is 6%. 6% of $12 is 72c. Now ... | |
| limit question | 9/10/2009 |
| Q: I'm not sure how to go about doing this problem. The limit as x-->infinity of (square root of ... A: The problem is lim(x->∞)[√(9x²+x)-3x]. Multiply by the conjugate, [√(9x²+x)+3x] ... | |
| Algebra | 9/10/2009 |
| Q: Hey could you help rationalize and simplify this expression √10/(√5-2) Thanks A: I will assume that this problem has a √5 - 2 in the denominator. The way to simplify problems ... | |
| Probablity | 9/10/2009 |
| Q: . i have a doubt in the below sum.. a)mean = np = 175(0.25) = 43.75 standard deviation = sqrt(npq) ... A: There is 0.5 on either side of the normal distribution. The normal table that was used gave the ... | |
| Calculus | 9/10/2009 |
| Q: .you have been a great help to me on a previous question. So, I hope you don't mind another: Find ... A: Is that O really a Θ? It looks like lim(Θ->0)(Θ²/(sin³Θ)). It is one of the ... | |
| College Algebra | 9/9/2009 |
| Q: One pipe can fill a tank three times as fast as another pipe. If together the two pipes can fill ... A: One pipe takes x minutes to fill the tank. The other pipe takes x/3 minutes to fill the tank. If 36 ... | |
| math combination | 9/8/2009 |
| Q: I have four 3-cent stamps and three 5-cent stamps. using one or more of these stamps, how many ... A: 1, 2, 3, or 4 3c stamps are 3c, 6c, 9c, or 12c. That is 4 sets of postage. If one 5c stamp is ... | |
| Percentages | 9/8/2009 |
| Q: An investor invests $100.00 at 2% and another $100.00 at 5%, he can determine the average by the ... A: Yes, it was right. I just made it look a little simpler. If it was a yes/no question on a test, I ... | |
| inches to gals | 9/8/2009 |
| Q: If I make a tank 22" x 35" x 6" how many gallons would that be ANSWER: Out of ... A: 2 x 35 is 70, 22 in. x 35 in. is (700 + 70) in² = 770 in². 7 x 6 = 42, so 770 in² by 6 in. is (4200 ... | |
| Calculus | 9/8/2009 |
| Q: How do you Evaluate the limit (6x^2 + 8)(6x + 3) as x approaches 6 ANSWER: The best way to evaluate ... A: We are given that f(x) = 2x^3. A. f(x+h) = 2(x+h)³ It is known that (x+1)³ = x³ + 3x^2 + 3x + 1, so ... | |
| Percentages | 9/7/2009 |
| Q: An investor invests $100.00 at 2% and another $100.00 at 5%, he can determine the average by the ... A: I modified what I received to make it look better. An investor invests $100.00 at 2% and another ... | |
| Calculus | 9/7/2009 |
| Q: How do you Evaluate the limit (6x^2 + 8)(6x + 3) as x approaches 6 A: The best way to evaluate limits is put in the value of x that the limit is approaching. To evaluate ... | |
| inches to gals | 9/6/2009 |
| Q: If I make a tank 22" x 35" x 6" how many gallons would that be A: Out of http://www.metric-conversions.org/volume/cubic-feet-to-us-liquid-gallons.htm?arg= I found out ... | |
| math | 9/6/2009 |
| Q: how do you find two sides of a triangle when you only have a side with no angles e.g i have the side ... A: Add 13-1 or 13+1 to 13. That's 13+12 or 13+14. The results of these two operations are 25 and 27. ... | |
| proof help | 9/5/2009 |
| Q: Prove that if 3<x(sub 1)<5 and x(sub n+1)= 2+ sqrt x(sub n)- 2. Then 3<x(sub n+1)< x(sub n) holds ... A: If x0 = 5, x1 = 2 + √(5-2) = 2 + √3. It is known that √3 is less than √4, ... | |
| supremums, and upperbounds proof | 9/5/2009 |
| Q: If you could please help me with this that would be wonderful! Prove that if x is the upperbound of ... A: Note that the supernum is the least upperbound. Is x is the upperbound of E, E is in R, and x is in ... | |
| Quantitative Analysis for Managerial Applications | 9/5/2009 |
| Q: 1.Write a detailed note on Normal Distribution, Standard Normal Variety and the Central Limit ... A: 2.From the following data compute quartile deviation and the coefficient of skewness: Size ... | |
| Statistics | 9/5/2009 |
| Q: Sir, Pl. solve the problem of the following:- Q:- Given the bivariate data: X 1 5 3 2 1 1 7 3 ... A: To solve both (a) and (b), you need to compute n, SX, SX², SY, and SY² where S is for the sum. There ... | |
| need a formula | 9/5/2009 |
| Q: we have X number of squares, each square can be connected only on a side (no diagonals)thus a square ... A: So with the cross there is one more. Like I said, it starts to get messy when there are only 5. If ... | |
| Application of Poisson distribution | 9/4/2009 |
| Q: Accidents occur on a particular stretch of highway at the rate of 3 per week. Find the probability ... A: According to the Poisson, with lambda=3, and 0 standing for no accidents, P(0) = (3^0)(e^-3)/0!. Now ... | |
| logarithms | 9/4/2009 |
| Q: 3log sub2 x= 2log sub2 8 A: The log sub 2 is the log in base 2, which is what power the number has. It is known that 8 = 2*2*2, ... | |
| need a formula | 9/4/2009 |
| Q: we have X number of squares, each square can be connected only on a side (no diagonals)thus a square ... A: There is a worksheet sent with all of the combinations. If you have ever played the computer game ... | |
| pre-calc help | 9/4/2009 |
| Q: how would you determine k and solve the equation: x^3-k2x^2+20x+12=0 A: First, what is that 2 doing between the k and the x? Usually constants go out front. It almost ... | |
| Prove | 9/3/2009 |
| Q: The arithmetic mean of a,b in R is A(a,b)=(a+b)/2, and the geometric mean of a,b in [10, infinity) ... A: a<G(a,b) Since a < b, multiply both sides by a, which is positive. The result is a^2 < ab. Taking ... | |
| graphing functions | 9/3/2009 |
| Q: sketch the graph of each function a) f(x)= absolute value of(x+3) -2 b) g(x)= 1/f(x) ANSWER: (a) ... A: a) f(x)= absolute value of(x+3) -2 b) g(x)= 1/f(x) To graph f(x), note that it is two lines with ... | |
| Difficulty with Stats & Probability | 9/3/2009 |
| Q: Am really please to have a tutor like you !! i have gone through with many illustrations you have ... A: I need to know the question. I will send some examples for you to look at, but there are even more ... | |
| graphing functions | 9/2/2009 |
| Q: sketch the graph of each function a) f(x)= absolute value of(x+3) -2 b) g(x)= 1/f(x) A: (a) The line would be at a perfect 45 degree angle with an upwards slope in both directions. |x+3| ... | |
| Quantitative Analysis for Managerial Applications | 8/11/2009 |
| Q: 1.Write a detailed note on Normal Distribution, Standard Normal Variety and the Central Limit ... A: 1. Here is the normal distribution: http://www.netmba.com/statistics/distribution/normal/ I only ... | |
| Division | 8/9/2009 |
| Q: The line below is divided into thirds: 2%______3%______4%______5% What is the line below divided ... A: Note that you've got the right idea. The first interval is from 2 to 3. 3 - 2 = 1, so there are 10 ... | |
| trigonometry | 8/9/2009 |
| Q: proving 1- cos2A/1=sinA=sinA sin2B/sec2B=cosB+cos2B tanB+1/cotB+1=tanB ... A: I'll take the 4th problem, which I haven't done yet, and give it a try. Show that tanA/(1+cotA) + ... | |
| trigonometry | 8/8/2009 |
| Q: proving 1- cos2A/1=sinA=sinA sin2B/sec2B=cosB+cos2B tanB+1/cotB+1=tanB ... A: I'd like to say thanks, but it's not that's doing anything. It's all in God's hands. I still see ... | |
| Division | 8/7/2009 |
| Q: The line below is divided into thirds: 2%______3%______4%______5% What is the line below divided ... A: There is a difference of 1% between each of the numbers in the first design. Since 5% - 2% is 3%, it ... | |
| Finding the average | 8/7/2009 |
| Q: Scott, This is a question from last year's math competition. I've looked over a few times, but I'm ... A: On messages that are to me, under private needs to be a, "Yes". As it is right now, Paul Klarreich, ... | |
| trigonometry | 8/7/2009 |
| Q: proving 1- cos2A/1=sinA=sinA sin2B/sec2B=cosB+cos2B tanB+1/cotB+1=tanB ... A: Yeah, I've had well over 3,000 questions in almost 2 years, but I've never had one from anybody with ... | |
| modulus function | 8/6/2009 |
| Q: how to settle such question.. |2x-3|<|x+1|..the answer given is 2\3<x<4.. |3x=1|<(4x+3)2(square) A: belle Country: Malaysia Category: Advanced Math Private: No Subject: modulus functionhow to settle ... | |
| expoenents | 8/5/2009 |
| Q: could u tell me whats the answer to this problem..and if it isnt to much to ask for..how did you get ... A: It is known that 1/2 is 0.5. This makes 2 and a half into 2.5 and 2 minus one half is 1.5. That ... | |
| abstract algebra | 8/5/2009 |
| Q: 1. The sum of u and v , denoted by u + v , is in V . 2. u + v = v + u . 3. (u + v) + w = u + (v + ... A: The reason they are needed is the same reason that multiplication is needed. After all, when you ... | |
| abstract algebra | 8/5/2009 |
| Q: 1. The sum of u and v , denoted by u + v , is in V . 2. u + v = v + u . 3. (u + v) + w = u + (v + ... A: I believe they are sometimes used to make problems simpler to solve, but they are necessary since ... | |
| abstract algebra | 8/4/2009 |
| Q: 1. The sum of u and v , denoted by u + v , is in V . 2. u + v = v + u . 3. (u + v) + w = u + (v + ... A: I'm not entirly sure of every answer, but I do have somewhat of a grasp of how to do them. Looking ... | |
| Circles | 8/4/2009 |
| Q: I have 2 different size circles , The radius of a circle is 2 cm , others 1 cm . At least how many ... A: Yes, you're right. It does barely cover the circle. I took a few minutes, wrote something down, ... | |
| pre-cal question | 8/3/2009 |
| Q: solve the equation: cos2x(2cosx+1)=0 in the interval [0,2) cos2x=0 2x=pi/2+2*pi*n x= ... A: When the first one is checked, note what is being done. First, x is being multiplied by 2. If x = ... | |
| Circles | 8/3/2009 |
| Q: I have 2 different size circles , The radius of a circle is 2 cm , others 1 cm . At least how many ... A: I have thought about this for awhile and realized that was a silly approach that I did. Now for each ... | |
| maths | 8/2/2009 |
| Q: can you please help me find a closed form for the sequence given by the recurrence syatem, giving ... A: This looks like A is indexed and the equation is A(0)=2400 A(n+1)=1.107*A(n-260). It is known that ... | |
| precalc | 8/1/2009 |
| Q: 3r= sin A, r and A represent polar coordinates. Write each polar equation as an rectangular ... A: If we look at the function x = ±√[(y-3y²)/3], we need 3y²<y for what's under the √ to ... | |
| Differentiation | 7/31/2009 |
| Q: Hey Scott Could you help me in finding the second derivative of the following implicit function ... A: Differentiate x^2-xy+y^2=7 implicitly. That gives 2x - xy' - y + 2yy' = 0. The value of y' can be ... | |
| Math | 7/31/2009 |
| Q: I have question in number theory but since all experts are on vacation in that field I thought you ... A: The rule for finding perfect numbers is by testing 2^n-1. If that is prime, then (2^n - 1)2^(n-1) ... | |
| pre-cal question | 7/30/2009 |
| Q: Find all solutions of the equation in the interval [0,2pi) sin(x+pi/6) - sin(x-pi/6)=1/2 Thank ... A: Here is where it is handy to use one of the trig identities. You know, the one about sin(A+B). It ... | |
| Maths | 7/30/2009 |
| Q: (1) X^2 + 3X + Y^2 = 404 (2) X + Y^3 = ? X and Y are positive integers. Find all possible ... A: I don't know of another way to do it besides trial and error. Basically, y² = 404 - x² - 3x means ... | |
| precalc | 7/30/2009 |
| Q: 3r= sin A, r and A represent polar coordinates. Write each polar equation as an rectangular ... A: Think about a triangle with the center at the origin. The point in question is the point at the ... | |
| pre-cal question | 7/28/2009 |
| Q: The monthly sales (in thousands of units) of a seasonal product are approximated by S= 74.50 + 43.75 ... A: The best way to do this is in a spreadsheet. In cell A1, put 1. In cell A2, put =A1+1. Highlight ... | |
| Plane Trigonometry | 7/28/2009 |
| Q: Having some difficulty with these problems and don't have a teacher to ask to explain them and show ... A: Now normally, I don't answer a question that requires this many answers. However, I only have two ... | |
| math | 7/28/2009 |
| Q: Sunshine Stereo sells cd players. The cd player lefe is normally distributed with a mean of 2.3 ... A: The average is 2.3 and the standard deviation is 0.4. Note that the cutoff point is 2, and this is ... | |
| Algebra | 7/27/2009 |
| Q: (2/a+3) - (3/2a+6) + (a+2/a^2+6a+9)=? ANSWER: That looks like it is 2/(a+3) - 3/(2a+6) + ... A: Oops - I'm not think straight today. That is really That is, (4a+12 - (3a+9) + (2a+4))/2(a+3)²) { ... | |
| Algrbra | 7/27/2009 |
| Q: If you reduce the numerator of the fraction (x+y)/(7x^2-7y^2) to UNITY, without changing the value ... A: You need to factor of 7x²-7y². Just looking at it, it can be seen to be 7(x²-y²). Now this is one ... | |
| Algebra | 7/27/2009 |
| Q: Solve the equation (ax/2b) - (c/3d) + x = 1 So.. x=? A: Get the x terms by themselves by moving anything without an x to the other side. The eqaution is ... | |
| Algebra | 7/27/2009 |
| Q: Simplify the complex fraction: (a-c/2a) / (a+c/2a) A: With that way I've been getting problems from you, I will assume that this is ... | |
| Algebra | 7/27/2009 |
| Q: (2/a+3) - (3/2a+6) + (a+2/a^2+6a+9)=? A: That looks like it is 2/(a+3) - 3/(2a+6) + (a+2)/(a²+6a+9). Notice the factors of the denominators. ... | |
| Algebra | 7/27/2009 |
| Q: Find the algebraic sum of the following: (2a+3b/3a) - (a-2b/4b) + (a^2+b^2/ab) A: That almost looks like it is suppose to be (2a+3b)/3a - (a-2b)/4b + (a^2+b^2)/ab. If it was the way ... | |
| Algrbra/Advanced Math | 7/27/2009 |
| Q: a^2 + 2/b divided by (a + 2/a)=? A: As written, a^2 + 2/b divided by (a + 2/a). Putting the numerator all over one number gives (ba^2 + ... | |
| About Complex numbers | 7/26/2009 |
| Q: the complex number w is given by w=-1/2 + i(3^1/2)/2. Find the modulus & argument of w. Thanks a lot A: Take the complex number as polar coordinates. The real part is the x value and the imaginary part is ... | |
| Verify differential equation | 7/26/2009 |
| Q: An underground storage tank is being filled with liquid as shown in the diagram.Initially the tank ... A: Take the right side of the equation, -20 + (2000)/((10-h)(10+h)). Multiply the terms in the ... | |
| trig question | 7/26/2009 |
| Q: Solve the equation tan3x(tanx-1)= 0 Thank you! A: Here is the corrected version. Note that the major correction is where I got sin^4(x), it should ... | |
| Integration | 7/25/2009 |
| Q: Hey, could you help in determining the following integral e^cosx*sinx Thank you. A: Let u = cosx. This makes du = -sinx dx, so -du = sinx dx. Take the integral ∫(e^cosx)sinx ... | |
| Problem using MS Excel | 7/24/2009 |
| Q: Let x and y be positive integers such that x^2 + 3x +y^2 = 404. What is the value of x + y^3? Find ... A: First, lets give the columns titles. In cell A1, put 404. In Cell B1, put X. In cell C1, put ... | |
| Intergration of Trigonometric Functions | 7/23/2009 |
| Q: Find the integral of cos^3x Thanks. A: There is one basic trig law that is learned in trig, but not used there much. However, when ... | |
| THE Math cont. | 7/22/2009 |
| Q: (Question 1) Assume a given pendulum has a period of 10 seconds on Earth. What is the length of the ... A: Question 1) Assume a given pendulum has a period of 10 seconds on Earth. What is the length of the ... | |
| Parentheses in multiplication - theory based | 7/22/2009 |
| Q: I'm asking a theory oriented question as opposed to an actual math problem. What is the basis for ... A: Yes, it is shorhand that is accepted to everyone who knows any math. Allowing 5x to be 5*x avoids ... | |
| The Math | 7/21/2009 |
| Q: Given the equation d=8cos((3pi/4)*t) for simple harmonic motion , find the maximum displacement. A: The cos() curve is known to vary from a minimum of -1 to a maximum of 1. The interval in which it ... | |
| Pre calculus help... | 7/21/2009 |
| Q: Establish each identity ! (1-cos^2 A) (1+cot ^2 A) = 1 i got as far as the second step (sin^2 ... A: Divide the entire equation by sin²A and you get 1 + cos²A/sin²A = 1/sin²A. It is known that ... | |
| trig | 7/21/2009 |
| Q: given: 0<or= X <360 degrees Solve: 1) 3tan 3X- square root of 3= 0 2) 3csc X/2 - 2square root of 3= ... A: 1) The problem is: 3 tan 3X - √3 = 0. This can be seen to be 3 tan 3X = √3, or tan 3X ... | |
| abstract algebra | 7/21/2009 |
| Q: Scott, I have an abstract algebra question. Given that componentwise addition of two elements in R^2 ... A: It is known that (a,b) + (c,d) is (a+b, c+d). It can be seen that phi(a,b) + phi(c,d) = (b,a) + ... | |
| Trigonometry | 7/20/2009 |
| Q: Establish the identity. (cos x/2 - sin x/2)^2=1 - sin x A: It is known that (cos x/2 - sin x/2)² = cos²x/2 - 2 sin x/2 cos x/2 + sim²x. Lets look at the left ... | |
| Trigonometry | 7/20/2009 |
| Q: Verify that the equation is an identity sin x+cos x/sin x- cos x=1+2sin x cos x/2sin^2x-1 A: I will assume this is really (sin x + cos x)/(sin x - cos x) = (1 + 2sin x cos x)/(2sin²x-1). ... | |
| pi | 7/20/2009 |
| Q: First of all, I am a layperson, and a pretty ignorant one at that, so pretend I'm a five-year old, ... A: Dimensions ------------------- pi is used in many dimensions. 1 If pi is being looked at in 1 ... | |
| Trigonometry | 7/20/2009 |
| Q: Write the expression in terms of sine and cosine, and simplify so that no quotients appear in the ... A: Multiplying by csc x gives cscx*sinx + cscx+cosx. It is known that csc x = 1 / sin x, so what we ... | |
| trig question | 7/20/2009 |
| Q: A passenger in an airplane flying at an altitude of 10km sees two towns directly to the left of the ... A: The altitude is 10 km. That is the far side on the triangle. The angles are 28 and 55 degrees. To ... | |
| % Solution problem | 7/19/2009 |
| Q: 1000 liters of a solution was 60% alcohol, however a 45% alcohol solution was needed. How many ... A: Note that 37% = 0.37. There are 1000 liters. It is 60% alcohol, so there are 600 liters of alcohol ... | |
| pre-cal | 7/19/2009 |
| Q: Solve for x. Write the answer in interval notation. 27 < 6x - 3(x - 9) < 54 2 A: Where is the 2 below the equation suppose to be? Is it suppose to be below the 3(x-9)? Lets just ... | |
| Trigonometry | 7/19/2009 |
| Q: What is the exact value of cos 22.5 degrees using a half angle id? A: We know that cos 45 degrees = rt(2)/2. It is also known that cos(a) = 2 cos^2(a/2) - 1. We know ... | |
| smallest surface area | 7/19/2009 |
| Q: Is it possible to work out the smallest surface area when you only have the following facts. You ... A: What gives the smallest surface area is a cube. This would be a little bit difficult to carry. To ... | |
| simplex algorithum | 7/18/2009 |
| Q: I searched simplex algorithum solver and put in the problem...came up with NaN??? Also, for Affine ... A: Yes, those are the answers to the math problem. I have no idea how to come up with a affine cypher. ... | |
| trigonometry | 7/16/2009 |
| Q: prove the following trigonometric identities: 1- cot^2/1+cot^2 = sin^2-cos^2 A: Since cot^2 is cos^2/sin^2, multiply the top and bottom by sin^2. Notet that cot^2*sin^2 = cos^2 ... | |
| abstract algebra | 7/16/2009 |
| Q: Scott, I have an abstract algebra question. Given that componentwise addition of two elements in R^2 ... A: A homomorphism is a function with the property that for some constant k and a point (x,y), ... | |
| angle of depression | 7/16/2009 |
| Q: find the angle of depression from the top of a lighthouse 250 feet above water level to the water ... A: One distance is 250 feet. The other is 2 miles. It is known that 1 mile is 5280 feet, so this ... | |
| advance math | 7/16/2009 |
| Q: 1.State the vertex of x2 – 2x – y = 0. 2.State the equation of the directrix of(y – 4)2 = –8(x – ... A: 1. State the vertex of x2 – 2x – y = 0. The vertex is where the minimum is. Since x^2 - 2x factors ... | |
| Proceeds | 7/13/2009 |
| Q: On June 30, 2007, Simon Company discounted a customer’s $180,000, 6-month, and 10 percent note ... A: Maturity What you did was calculate the amount of interest paid at the time of maturity. However, ... | |
| calculus | 7/13/2009 |
| Q: Find the indicated term of the sequence : 1. an = 5n + 6/n-6 a12 = ... A: 1. a12 = (5(12) + 6)/(12-6) = n66/6 = 11. 2. Now n2/2 is just n. Is that suppose to be n²/2? a20 = ... | |
| Maths Question | 7/13/2009 |
| Q: What is the smallest number that is divisible by 2,3,4,5,6 and when you divide it has a single digit ... A: The smallest number that can be divided by 2, 3, 4, 5, and 6 that has a single digit left over is 7. ... | |
| algebra help please? | 7/12/2009 |
| Q: 22. y/y+2 – 2/ y+3= 10/ y^2+y-6 a) y= -2 or 3 b) y=0 or -2 c) y= 2 or -3 d) not given ... A: 22. I'll assume the problem is really y/(y+2) - 2/(y+3) = 10/(y²+y-6). It can be seen that y²+y-6 ... | |
| Similarity Problem | 7/12/2009 |
| Q: I've got a maths problem: Let ABC be a triangle. Two straight lines which are parallel to the side ... A: Let C be the top of every triangle mentioned. The area of any such triangle will be kl² where k is ... | |
| proving by induction! | 7/12/2009 |
| Q: my question is how to prove by induction that for every n ≥ 1 or 2, fib(3n) is even, that is, ... A: Let us assume that for some n that fib(3n) is even, f(3n+1) is odd, and f(3n+2) is odd. Since we ... | |
| abstract algebra | 7/11/2009 |
| Q: Scott, I have an abstract algebra question. Given that componentwise addition of two elements in R^2 ... A: onto Let us pick some random point (a,b). To get to that point, take the point (b,a) and look at ... | |
| volume of washer in sq. in. | 7/11/2009 |
| Q: "Item is 1.895 O.D. x 1.625 I.D. x .437 thk. What is volume? Answer needs to be in square inches." ... A: From what I understand, O.D. is outside diameter and I.D. The volume would be π(R²-r²)T where R ... | |
| Investment Profit - Percentage | 7/10/2009 |
| Q: An investor invest $100.00 for one year at simple interest. At the end of one year his investment ... A: Yes, the profit is $50. If the fee were charged on the original $100, it would be $2.50. If the ... | |
| Investment Profit - Percentage | 7/10/2009 |
| Q: An investor invest $100.00 for one year at simple interest. At the end of one year his investment ... A: Is the 2.5% fee only on the $50.00 that he made? In that case, 2.5% is the same as 2.5/100 = ... | |
| Double angle | 7/10/2009 |
| Q: I know part i) but part ii) i only finished halfway because i dont know how to find a. i) express ... A: To get the second angle, look at the sin() wave. It is symmetrical around 90 degrees. For example, ... | |
| abstract algebra | 7/10/2009 |
| Q: I need to explain using abstract algebra how to geometrically construct a square with an area equal ... A: The is a way to find an angle that is 1/3 of an angle less than 90 degrees. ... | |
| calucus | 7/9/2009 |
| Q: Write the first four terms of the sequence. (Assume n begins with 1) 1. an = 3n + 7 2. an = 3n + 1 ... A: 1. The terms area 3n + 7. If the sequence is 3n + 7, the first four terms are 3(1) + 7, 3(2) + 7, ... | |
| Double angle | 7/9/2009 |
| Q: I know part i) but part ii) i only finished halfway because i dont know how to find a. i) express ... A: For part 2, we know that 5 sin 2A + 12 cos 2A = 11 for A between 0 and 180 degrees. It is also ... | |
| Algebra | 7/9/2009 |
| Q: If the fractions ax/x+y), (bx/x-y) and (c/2x+2y) are rewritten as equivalent fractions with the ... A: The 1st fraction has an (x+y) in the denominator. The 2nd fraction has an (x-y) in the denominator. ... | |
| Algebra | 7/9/2009 |
| Q: -4a^2b/3x x ax/bc- A: Is this problem (-4a²b/3x)(ax/bc)? Is so, here is what I see: Constants: There is a -4 in the ... | |
| Mechanics on Kinematics | 7/7/2009 |
| Q: A train travels from A to B,a distance of 20000m,taking 1000s.The journey has 3 stages.In the first ... A: Note that I don't know if there is an exact answer. I am sending you what I have worked out so far. ... | |
| Probability Question | 7/7/2009 |
| Q: Assume playing blackjack with a basic blackjack strategy which will win 48% of the hands. Also ... A: Each time the game is played is independent of the last. So if you have already lost 5 in a row, ... | |
| Pascal's triangle | 7/6/2009 |
| Q: I don't understand this.... Find a relationship between entries in Pascal's triangle and the maximum ... A: Now Pascal's triangle I'll start with row 0, which is 1. Row 1 can be seen to be 1 1. Row 2 can be ... | |
| permutation and combination | 7/5/2009 |
| Q: 1)A coin is tossed 14 times.Heads occurs 8 times and tails 6 times.The second and thirteen tosses ... A: 1) It is known that a head occurs on the 2nd and 13th flips of a coin. It is also known that a ... | |
| abstract algebra | 7/4/2009 |
| Q: Scott, I have an abstract algebra question. Given that componentwise addition of two elements in R^2 ... A: An automorphism is an invertible linear transformation. In this case, the automorphism is in 2 ... | |
| Statistics | 7/4/2009 |
| Q: Why is the standard deviation used to get the 'average' deviation between a data value and the mean ... A: Take three number sets. Set A: 1,2,3 Set B: 2,3,4 Set C: 1,2,2,3,3,4 Now it can be seen that set C ... | |
| Line of intersection of 2 plane | 7/4/2009 |
| Q: Two planes have equations 2x-y-3z=7 & x+2y+2z=0.Find a vector equation for their line of ... A: Let z = a. The two equations become 2x - y = 7 + 3a and x + 2y = -2a. The right sides are ... | |
| Matrix representaton of transformations | 7/3/2009 |
| Q: I recently learned in my undergrad linear algebra class that any linear transformation performed on ... A: I'm a little rusty at Laplace Transforms, but from what I know, a Laplace Transform is not worried ... | |
| volume of odd shaped pyramid | 6/25/2009 |
| Q: I'm trying to calculate the volume of a solid that is similar to a pyramid. If you picture the base ... A: The volume of a pyramid is Ah/3 where A is the area of the base and h is the height. I had to think ... | |
| Scale | 6/25/2009 |
| Q: Plastic model kits are reduced to a scale from the original much larger version. For example, on a ... A: This scale indicates that every inch of the model aircraft is equivalent to 32 inches on the plane. ... | |
| trig. | 6/25/2009 |
| Q: 3)Sketch the angle in standard position, indicating its rotation by a curved arrow. Choose the ... A: I take measurements between 0° and 90° to be in quadrant I 90° and 180° to be in quadrant II, 180° ... | |
| statistics in testing | 6/25/2009 |
| Q: why correlation coeficient in testing validity of a parallel test never become negative?it's always ... A: The correlation coefficient is how much interaction there is between the variables and is known as ... | |
| trigonometry | 6/24/2009 |
| Q: how do i simplify cos(1/2sin^1(7/25)) without using a calculator? A: Simplify cos(1/2sin^1(7/25)) without using a calculator. That is better written as ... | |
| Inequalities | 6/24/2009 |
| Q: Given: a^2 + b^2 =1 ; c^2 + d^2 = 1 Prove; ac + bd is equal to or less than 1 A: Let's look at the function a^2 + b^2. O put the variable a in a spreadsheet from 0 to 1 by 0.1, in ... | |
| Right Triangle Trigonometry | 6/23/2009 |
| Q: Given right Δ ABC with <C = 90°, a = 12, b = 5 , find the indicated trig function in simple ... A: It is known that the tan() is the oppositve over the adjacent. Since side a is opposite angle A, a/b ... | |
| Proving Identities | 6/23/2009 |
| Q: Sinx(secx+cscx)=tanx+1 ANSWER: Multiply the left side out and you get sinx secx + sinx cscx. Since ... A: Take sin^4A - cos^4A. Replace one of the two sin^2A in the first expression with 1 - cos^2A. ... | |
| Proving Identities | 6/23/2009 |
| Q: Sinx(secx+cscx)=tanx+1 A: Multiply the left side out and you get sinx secx + sinx cscx. Since secx = 1 / cosx and cscx = 1 / ... | |
| calculus | 6/22/2009 |
| Q: 1.find the exact refernceandle for 6pi/7 2.convert5pi/4 radians into degree measure 3.Find the value ... A: 1.find the exact refernceandle for 6pi/7 The reference angle is between 0 and π/2. If it is ... | |
| calculus | 6/22/2009 |
| Q: 1.Find the exact reference angle for 4pi/7 2. Find the exact value of tan(arccoss 3/5) 3.Find the ... A: 1.Find the exact reference angle for 4π/7 The reference angle is between 0 and π/2. Since ... | |
| Pre calculus | 6/22/2009 |
| Q: 1. log3x-log3(x-3)=2 2.log2x-log2(x-2)=3 3. 2^x=6 4. e^x+3=8 5.log13x/5 6. log381=x A: 1. It is known that with log, subtracting two is the same as dividing the insides. In other words, ... | |
| pre calc | 6/21/2009 |
| Q: So out of 5 assignments these were the only ones i got stuck on. Can you show me the steps?? 1. ... A: 1. Find the length of v given that the initial point of v is (0,-1,0) and the final point of v is ... | |
| Polar and Rectangular form | 6/21/2009 |
| Q: 1. Convert x=a to Polar form. 2. Convert r=4 cos theta into rectangular form. 3. Find the ... A: Polar is (r, Θ) and rectangular is (x, y). The relation between them is r² = x² + y² and ... | |
| About Normal distribution | 6/20/2009 |
| Q: 400 pupils sit a test which consists of 80 true-false questions. None of the candidates knows any of ... A: Yes, n should be 80, for that is the number in each test. Now to solve part a, n is 80 and p is ... | |
| Standard normal variable | 6/20/2009 |
| Q: A certain tribe is distinguished by the fact that 45% of the males have 6 toes on their right foot. ... A: I have all four problems answered and will be sending them shortly. Unless of course something else ... | |
| De-standardising | 6/20/2009 |
| Q: Two hundred fair dice are thrown 1000 times. Use the normal approximation to the binomial ... A: Since there are only 200 choices, 200*6 is 1200, which is far more than 200. You use 200/6 because ... | |
| Continuity correction | 6/20/2009 |
| Q: A lorry load of potatoes has, on average, 1 rotten potato in 6. A greengrocer tests a random sample ... A: I was 1/6 since one of of 6 potatoes is bad. If she finds 18 or less, the lot is accepted. The ... | |
| Your Opinion | 6/20/2009 |
| Q: I was wondering if you would be able to help me out. You see, I am going into high school and enjoy ... A: I believe you should study hard at what interests you. However, don't just study hard at math. Be ... | |
| dice probability question | 6/19/2009 |
| Q: Complete the probability distribution table for the experiment of rolling a pair of dice until a sum ... A: There is 1 way to roll a 12, 2 ways to roll and 11, 3 ways to roll a 10, 4 ways to roll a 9 and 5 ... | |
| Trig | 6/18/2009 |
| Q: Find exact value of sin2theta, cos2theta, tan2theta for the angle described: costheta=24/25 ... A: FOr cos(Θ)=24/25 and the angle is in quadrant IV means y is negative. It also mean that x=24 ... | |
| precaluculus | 6/18/2009 |
| Q: 1.f(x)=x2-4 2.y=3x+2 3.f(x)X2-6x 4.f(x)=x/x2-4 5.f(x)= 3x2+5x when f(x)=2.....please asap A: I'm not sure exactly what is being sought, but given that this is pre-calculus, I bet that it is ... | |
| Hello | 6/18/2009 |
| Q: Scott, I need help with these. Can you please help? 1) Convert (10011110)^2 to a hexadecimal ... A: The ^ is usually reserved for powers. What if you said (10011110)B2 as 10011110 in base 2 or ... | |
| Probability | 6/17/2009 |
| Q: The telephone company has run out of seven-digit telephone numbers for a new area code. Find the ... A: The first digit cannot be 0 or 1 means there are only 8 possibilities for the first digit and 10 for ... | |
| precalculus | 6/17/2009 |
| Q: Solve for x : 1. 4x+1 = 64 2. log 10 x – 2 = 0 3. ln x – ln 5 = 0 4. ( ½ )x ... A: 1. 4x+1 = 64, subtract 1 from both sides, giving 4x = 63, divide both sides by 4. 2. log 10 x ... | |
| Precalculus | 6/17/2009 |
| Q: Evaluate the expression without a calculator : 1. log 4 64 2. log 5 ( 1/25) 3. log ½ 16 4. log ... A: Evaluate the expression without a calculator : 1. log 4 64 The problem is 4^x = 64, and that is 3 ... | |
| Precalc help | 6/17/2009 |
| Q: I'm totally lost, can you please please explain this problem. x^2-9y^2=9 list the x and y ... A: The y intercepts would be where x is 0. This means that -9y^2 = 9, or y^2 = -1, which is not ... | |
| Number Systems | 6/17/2009 |
| Q: For which number system is this true for (a+b)^2 = a^2 + b^2 A: If the right side is squared out, the answer is a^2 + 2ab + b^2. So we have a^2 + 2ab + b^2 = a^2 + ... | |
| Accounting | 6/15/2009 |
| Q: Question CP2-1 Determining Financial Statement Effects of Various Transactions: L01, L02 Lester's ... A: The total credits are $40,000 sale of stock and $4,000 sale of land. The total is $44,000. The ... | |
| Harder Examples of the Binomial Theorem | 6/14/2009 |
| Q: So the question is "What is the coefficient of (x^7) in the expansion ((1+2x)^4)((1-2x)^6). We were ... A: The coefficients are the numbers in Pascal's triangle. For n = 4, they are 1 4 6 4 1. For n = 6, ... | |
| Solution of linear equations | 6/13/2009 |
| Q: Use Gauss or Gauss-Jordan elimination to find for what value of k the following system of equations ... A: See the attached image. It has no solution when any of the expressions for k in the final matrix ... | |
| About Normal distribution | 6/13/2009 |
| Q: 400 pupils sit a test which consists of 80 true-false questions. None of the candidates knows any of ... A: There are 400 pupils, 80 questions per test. The average number of correct answer is 1/2, so the ... | |
| Standard normal variable | 6/13/2009 |
| Q: A certain tribe is distinguished by the fact that 45% of the males have 6 toes on their right foot. ... A: Again, the binomial is being approximated with the normal. The number n is 200. The probability p ... | |
| De-standardising | 6/13/2009 |
| Q: Two hundred fair dice are thrown 1000 times. Use the normal approximation to the binomial ... A: There are 200 dice, thrown 1000 times. The expected number of 6's in each toss is 200/6 = 100/3. The ... | |
| The Normal approximation to binomial distribution | 6/13/2009 |
| Q: in a series of n independent trials the probability of a 'success' at each trial is p. If R is the ... A: For (a), the binomial can be used. Calculate it for k = 3. For (b), calculate 1 - P(all red). ... | |
| Continuity correction | 6/13/2009 |
| Q: A lorry load of potatoes has, on average, 1 rotten potato in 6. A greengrocer tests a random sample ... A: Use n = 100 and p = 1/6, so 1 - p = 5/6. Approximate this with a normal distribution. The mean is ... | |
| The normal distribution | 6/13/2009 |
| Q: When i look at the question, my head totally blank. I'm stuck, i cant work out which is n which is ... A: a) The number of times is 200; the chance of a 6 is 0.25. i) the chance of more than 60 can be ... | |
| adding different bases but same exponent | 6/13/2009 |
| Q: a^x = b^x (a and b are arbitrary constants). Easy enough to solve for x, right? But what about: a^x ... A: Previous Answer: It has been shown that this equation can't be solved for x > 2 since the form is ... | |
| finding rule from function table | 6/11/2009 |
| Q: I'm in the 6th grade and I cannot find the rule from the follwing table. x=1, 5, 9 y=5, 1, -3 I ... A: The values of x were 1, 5, and 9. The values of y were 10, 8, and 6. Note that the numbers must be ... | |
| finding rule from function table | 6/11/2009 |
| Q: I'm in the 6th grade and I cannot find the rule from the follwing table. x=1, 5, 9 y=5, 1, -3 I ... A: What you are missing is that you need to look at the differences between each consecutive element. ... | |
| solving inequalities | 6/10/2009 |
| Q: can you solve this problem n^2*5 fraction bar> ----->9.5 5^2 ANSWER: ... A: I put 7 in Excel, and I got 9.8. The formula I used was putting a 7 in A1 and putting a =A1^2*5/5^2 ... | |
| solving inequalities | 6/10/2009 |
| Q: can you solve this problem n^2*5 fraction bar> ----->9.5 5^2 ANSWER: ... A: The last problem had what I thought was a typo, and you just clarified it to make sure my ... | |
| solving inequalities | 6/10/2009 |
| Q: can you solve this problem n^2*5 fraction bar> ----->9.5 5^2 ANSWER: ... A: In that case, you have 5n²/25 > 9.8. { I like to put 5n^2 (5n²) rather than n^2*5, so that it is ... | |
| solving inequalities | 6/10/2009 |
| Q: can you solve this problem n^2*5 fraction bar> ----->9.5 5^2 A: I'm not sure exactly on the problem, since this langue does not translate multiple line correctly. ... | |
| math learing problems | 6/10/2009 |
| Q: i have a question for you I have a real hard time with math,I have a learing disablity know as ... A: Note: Though this question was to me, it wan't private, which means others will see who it was to. ... | |
| Transposing/ Subject of formula | 6/9/2009 |
| Q: S=U+1/2gtsqured making "t" the subject A: Is that formula suppose to be S = U + gt²/2? To solve for t, first move every expression that has ... | |
| math | 6/9/2009 |
| Q: Convert 890mm to centimeters. A.0.89cm B.8.9cm C.89cm D.8.900cm A: I is known that the European measuring system is like, I say, user friendly. 10 mm = cm, 10 cm = ... | |
| Subtracting Decimals | 6/9/2009 |
| Q: I am trying to figure how to solve decimals with nothing to borrow from. Ex... 0.0025 - 0.075, 0.9- ... A: The best way to subtract a large number from a smaller number is to reverse them. When finished, ... | |
| advanced algebra | 6/8/2009 |
| Q: standard deviation of 10,10,54,39,96,91,91,18 A: To find the standard deviation, other things must be done first. The number of values is 8. The ... | |
| Trigonometry: Polynomial Functions | 6/7/2009 |
| Q: Determine the equation of the given function f(x)=k(2x-3)(x+4)(3x-5)(x-10) ? Also, if I am given ... A: The graph would cross the axis every where x is 0. This can be seen by looking at each set of ... | |
| math | 6/7/2009 |
| Q: Find the value of the expression by using logarithms. 1.05^(9) A.0.15514 B.1.5514 C.80.742 D.9.45 A: The 1.05^9 is the sames as e^(ln(1.05^9)) since e^x and ln(x) are inverses of each other. When the ... | |
| Geometric Sequences | 6/6/2009 |
| Q: I need help with the followingFind all the geometric sequences such that the sum of the first two ... A: A geometric series is a, ab, ab² where a is a constant and b is a number to a one higher power each ... | |
| sequence for calculating flea populations. | 6/5/2009 |
| Q: As a vet I'm constantly trying to explain the population growth rates for fleas reproducing under ... A: I designed a program for you in C++. It assumes that there are 2 fleas to start with (doesn't it ... | |
| Calculus Problem | 6/5/2009 |
| Q: I am having difficulty solving this problem. Could you please help explain the solution to me step ... A: The answer would depend on the area of the cone in the cross section at that height. Since the ... | |
| math | 6/5/2009 |
| Q: Find the value of the expersion by using logarithms. 7.864^(1.405) A.2.3053 B.11.049 C.18.129 ... A: Using logarithms, it is known that 7.864^(1.405) = e(ln^(7.864^(1.405))). With ln, you can take ... | |
| Calculus | 6/4/2009 |
| Q: what is the integral of sqrt(x^2+3)dx using ln? A: Such a small little problem with such a big solution... I tried u = ln(x), ln(u) = (x²+3)^0.5, and ... | |
| Trig identities | 6/4/2009 |
| Q: csc2x-cot2x=tanx A: It is known that csc2x = 1/sin2x = 1/(2sinxcosx). It is known that cot2x = cos2x/sin2x = ... | |
| Solving Sequence related math problems | 6/4/2009 |
| Q: .. I am preparing for my SAT in three days and I have been out of highschool for nearly 4 years. ( I ... A: Sorry about that, so here is the right answer. The 1st number is 3. 1st is odd, so add 2. This ... | |
| Curve Sketching | 6/4/2009 |
| Q: this is my first time posting on this board. Let me first off just say Great Service! I was just ... A: Known facts laid out easy to read: f(-2) = 8 f(0) = 4 f(2) = 0. f'(x) > 0 for |x| > 2 f'(x) < 0 for ... | |
| math | 6/4/2009 |
| Q: Use logarithms to solve problem Divide 0.05555 by 0.0008601 A.0.015484 B.0.04778 C.64.584 D.6.4584 A: N1 0.05555 First number given N3 0.0008601 Second number given N3 -2.890471763 ln(N1) ... | |
| math | 6/4/2009 |
| Q: On a certain street, a section having an area of 4896.7 square yards is paved at an expense of ... A: Take the $12,642.17 and divide it by 4896.7 to get the price per yard. This comes out to around ... | |
| Pre-calculus | 6/4/2009 |
| Q: Deduce the Equation: 2aX=-b+or-(b*2-4ac)*1\2 If ax*2+bx+c=0 A: Take ax² + bx + c = 0 and subtract the c from both sides giving ax² + bx = -c. Factor out the a, ... | |
| Trigonometric Identities.. | 6/4/2009 |
| Q: Prove that for all θ, tan² θ / sin² θ = 1 + tan² θ, then check the identity ... A: It is known that tanΘ = sinΘ/cosΘ. Squaring both sides gives us tan²Θ = ... | |
| please help!! | 6/4/2009 |
| Q: 3x+y-2z=10 6x-2y+z=-2 x+4y+3z=7 solve the system. A: Convert this into the augmented matrix and get R1: 3 1 -2 10 R2: 6 -2 1 -2 R3: 1 4 3 7. Now since ... | |
| Proving Identities | 6/3/2009 |
| Q: I have 3 identities that cannot prove...here they are... X=theta ^2=squared ^3=cubed tan X-(sec^2 ... A: tan X-(sec^2 X/tan X)=-cot X On the first one, it is known that tanX = sinX/cosX and sec²X = ... | |
| Solving Sequence related math problems | 6/3/2009 |
| Q: .. I am preparing for my SAT in three days and I have been out of highschool for nearly 4 years. ( I ... A: The 1st term is 3. The 2nd term is 5. The 3rd term is -2nd term = -5. The 4th term is -5+2 = 3, ... | |
| trigs | 6/3/2009 |
| Q: prove that: tan(x/2+ pie/4) = secx + tanx (i could find the symbol for pie so i used the word ... A: This problem has two parts. The first part is that the angle is (X + pi/2)/2. It is known that ... | |
| math | 6/3/2009 |
| Q: Find the numbers corresponding to the given logarithms. 9.27631-10 A.1.8893 B.0.18893 C.0.018894 ... A: First, we need to compute 9.27631-10. It is found to be x. Once that value is gotten, compute 10^x. ... | |
| math | 6/3/2009 |
| Q: Find the corresponding to the given logarithms. 0.81293 A.0.65003 B.0.62007 C.6.5003 D.6.5007 A: I wasn't sure what was meant, so I did the following: Given the numbers A 0.65003 B 0.62007 ... | |
| algebra simplification | 6/3/2009 |
| Q: x^4+y^4 divided by x-y A: It is best if this is done by quasi-long division. If we let the x^4 + y^4 be a set of numbers such ... | |
| Integration Problem | 6/3/2009 |
| Q: I'm trying to solve the following integral: integral t^2 / sqrt(t-1) dt I have tackled this problem ... A: If we let u = √(t-1), then du = 1/√(t-1) dt. Notice that 1/√(t-1) is in the ... | |
| Geometry type problems. | 6/3/2009 |
| Q: I have more than one question & if it's possible, I would like to know the steps to each question ... A: ON new questions, it is best to send another letter, now a follow up. I almost didn't answer right ... | |
| math | 6/2/2009 |
| Q: What are the logarithms of the numbers? 2346 A.2.37033 B.3037033 C.4.37033 D.5.37033 A: I believe the answer to be B, but it looks like a typo was made. The log(2346) = 3.37033. Is that ... | |
| Geometry type problems. | 6/2/2009 |
| Q: I have more than one question & if it's possible, I would like to know the steps to each question ... A: That was silly to think of it as time. I should have realized that it was 12 to 30. Since both ... | |
| Mathematics of finance | 6/1/2009 |
| Q: My name is Ben and I am having a problem answering a question in my finite math course. A 1000 ... A: The interest rate of 3% compounded monthly is (3%/year)(year/12 months) = 0.25%/month. That's the ... | |
| Tangent Table for Obtuse Angles | 6/1/2009 |
| Q: Is there a table that shows the tangents for obtuse angles, and if so is there a website I can go ... A: It is known that the tan() of an angle large than 90° is 1 over the tangent of 180° - the angle in ... | |
| Geometry type problems. | 6/1/2009 |
| Q: I have more than one question & if it's possible, I would like to know the steps to each question ... A: Percentages are just like decimals with the decimals slid over 2 places. For example, 0.5 is really ... | |
| algebra | 6/1/2009 |
| Q: 7/2x + 1/2x = 3x + 10/2 + 7/2x A: 7/2x + 1/2x = 3x + 10/2 + 7/2x Is the problem suppose to be 7x/2 + x/2 = 3x + 10/2 + 7x/2? I've ... | |
| algebra 2 | 5/31/2009 |
| Q: how do you solve the equation log(4)(2x-6)=3 A: Since there is a log(4) out front, divide both sids by log(4). That gives 2x - 6 = 3/log(4). After ... | |
| Proving Trig Identities | 5/31/2009 |
| Q: I was having afew problems with some questions I why given to do. How do you prove the following? ... A: Note the following identities: sin²(x) + cos²(x) = 1; tan(x) = sin(x)/cos(x); cot(x), which I ... | |
| Integration | 5/31/2009 |
| Q: Find the area of the region enclosed between the curves y=x^2 and y=2^x and the lines x=1 and x=5. A: To find the area between two curves, find out if they intersect in the region given. Here, the ... | |
| Advanced Math | 5/31/2009 |
| Q: A car dealer sells a SUV for $39,000, which represents a 25% profit over the cost. What was the cost ... A: If the amount over cost is 25%, that is 1/4 of the cost. The original cost has a factor of 1 = 4/4. ... | |
| Integration | 5/30/2009 |
| Q: Find the area of the region enclosed between the parabola y=3x^2+x+1 and the line y=3-4x. Thanks ... A: First we need to find where the two curves intersect. Setting them equal gives 3 - 4x = 3x² + x + 1. ... | |
| math | 5/30/2009 |
| Q: A person invested $10,000. The greater part is invested at 6% and the remainder at 5%. The annual ... A: Since we are looking for the smaller part, lets call that x. The larger part would be 10,000 - x. ... | |
| math | 5/30/2009 |
| Q: Which one of the following is an intermediate step if the given equations are to be solved by ... A: To eliminate a variable, the need to have the same coefficient out front with opposite signs. In A, ... | |
| math | 5/30/2009 |
| Q: A bicyclist and a hiker leave the same place at the same time and travel in the same direction. The ... A: The biker travels 3 times as fast as the hiker. At the end of 3 hours, they are 24 miles apart. ... | |
| pre caluculus | 5/29/2009 |
| Q: Find the equation of the asymptote for f(x)=e^x -2 and use a limit expression to describe the ... A: To find the assymptote of f(x) = e^x - 2 using limits, take lim h->0 of (f(x+h)-f(x))/h. That is, ... | |
| math | 5/29/2009 |
| Q: How is the following system of equations classified? 9x-3y=24 y=3x-8 A.Dependent ... A: I believe it is best to solve for y and then compare them in this case. For the first, subtract 9x ... | |
| The Binomial THeorem | 5/29/2009 |
| Q: The question asks to find the coefficient of x^6 in the expansion of (2+x)(4-3x)^16. I manage to ... A: The coefficient on x^6 would be the sum of two coefficients. It would be 2*(coefficient on x^6) + ... | |
| math | 5/29/2009 |
| Q: What mulitplier should be used for each of the following equations to eliminate one unknown by ... A: The coefficients of x are 3 and 2, and the same sign, so the first equation could be multiplied by ... | |
| exponential equations | 5/29/2009 |
| Q: I have a question which I havent been able to answer. My teacher gave me my final last week and I ... A: Use Excel. Put 0 in A1, 2 in A2. Put =A1-B1*(A2-A1)/(B2-B1) in A3. Put =2^A1+2^-A1-3 in B1. Copy ... | |
| Addition of probabilities | 5/28/2009 |
| Q: A bag contains 10 counters,of which 6 are red & 4 are green.A counter is chosen at random;its colour ... A: P(R) = 6/10 = 3/5. P(G) = 4/10 = 2/5. P(R,R) = (3/5)² = 9/25. P(R,G) = (3/5)(2/5) = 6/26. P(G,R) = ... | |
| Conditional probability | 5/28/2009 |
| Q: The chevalier du mere problem.A seventeenth-century french gambler,the chevalier du mere,had run out ... A: The chance of a 6 is 1/6. The chance of 2 6's is (1/6)(1/6) = 1/36. The chance is the same on each ... | |
| Independent events | 5/28/2009 |
| Q: Two chess players,k1 & k2,are playing each other in a series of games.The probability that k1 wins ... A: Construct a tree with 3 branches. Branch 1 is a draw with a probability 0.5. Branch 2 is k1 wins and ... | |
| Alg. 2 | 5/28/2009 |
| Q: 1. What is the most possible number of solutions of one circle and a straight line in the same ... A: 1. What is the most possible number of solutions of one circle and a straight line in the same ... | |
| Probability | 5/28/2009 |
| Q: I know how to do part a) but i dont know how to do part b). Please guide me in part b.a)calculate ... A: It looks like part b is to calculate the number of numbers over 800. To be greater than 800 out of ... | |
| Variance | 5/28/2009 |
| Q: a bag contains 5 identical discs, 2 of which are marked with the letter A & 3 with the letter B. The ... A: There are 5 discs, only 2 red. Now C(n,k) was defined to be n!/(k!(n-k)!)). The chance of getting ... | |
| Expectations & variance | 5/28/2009 |
| Q: In the mass production of a certain component it is found that 5% are defective. Components are ... A: Since 5% are defective and each box contains 10, we need the probability that each box contains no ... | |
| Special discrete probability distributions | 5/28/2009 |
| Q: In a bag there are 6 counters, 8 yellow counters & 6 green counters. A counter is drawn at random ... A: Now the problem states 'In a bag there are 6 counters, 8 yellow counters & 6 green counters.' I ... | |
| math | 5/28/2009 |
| Q: Solve the following equations 4ax+by=11ab 8ax-5by=ab A. x=3a,y=2b B. ... A: It can be see that if the first equation is multiplied by -2 and added to the the second equation, ... | |
| Empty Sets | 5/19/2009 |
| Q: Hey there, Scott. I'm a college student who has never really grasped the concept of an empty set. I ... A: The number 0 is a number. It can be treated like any ohter element. If a set has an element, its ... | |
| trignometry | 5/19/2009 |
| Q: a tree 12 meter high is broken by the wind in such a way that its top tuches the ground and makes an ... A: Oh yeah, now and then I goof up and do one wrong. The angle is 60° with the ground. That means the ... | |
| math | 5/19/2009 |
| Q: Find the least common denominator of the fractions. (1)/5a^2x, (1)/12a^3x^2, and (1)/2ax^4 A: I assume the fractions are 1/(5a^2x), 1/(12a^3x^2), and 1/(2ax^4). Common Factors ... | |
| proving trig identity | 5/19/2009 |
| Q: cos2x/1+sin2x = cotx-1/cotx+1 A: The question on the right side is (cotx - 1)/(cotx + 1). So lets take the and make it look lie ... | |
| math | 5/19/2009 |
| Q: 5a-4/3x^2 MULTIPLY BY x/25a^2-16 = A: Do you mean [(5a-4)/3x^2][x/(25a^2 - 16)]? I believe you do, so what we get is by mulitplying ... | |
| coefficent | 5/18/2009 |
| Q: what is the coefficient of k when -8p+k(3^3+5*2)+6k-3(4k+9) A: To get the coefficient, multiply it out and look for terms with k. The expression, ... | |
| math | 5/18/2009 |
| Q: 3 multiply by 2a/5c multiply by cd/ab = A: Is that 3(2a/5c)(cd/ab)? The answer is 6d/5b. I've gotten use to that meaning 6d divided by 5b. ... | |
| arithmetic | 5/18/2009 |
| Q: A number K, is a positive integer with the special property thet 3 times its unit is equal to 2 ... A: Take the number as NM, two digits, in between 10 and 99. There are N 10's and M 1's. It says that ... | |
| 10% Profit | 5/18/2009 |
| Q: An investors buys 100 shares of stock where he is employed at $50.00 per share. Brokerage commission ... A: To buy 100 shares when the price is $50 per share is %5000. He pays $20 when buying them and $20 ... | |
| math | 5/17/2009 |
| Q: Solve the equation: 0.9x+0.5 = 0.4x+2.5 A: To solve the equation, put the x's on the left and the constants on the right. This is how to sove ... | |
| function for a graph | 5/17/2009 |
| Q: can you find me a function for r=1 [a circle] an x parameter[it represents angles from 0 to 360] and ... A: If the point is on the circle with radius r, angle Θ, and x1 is in the x direction and x2 is in ... | |
| function for a graph | 5/17/2009 |
| Q: can you find me a function for r=1 [a circle] an x parameter[it represents angles from 0 to 360] and ... A: Do you mean polar coordinates? In polar coordinates, r is the distance from the origin and Θ ... | |
| math | 5/17/2009 |
| Q: Simplify the following expression: [(32ab-8cd+20ef)divide by 2]+2xy A: The expression is [(32ab-8cd+20ef)divide by 2]+2xy. To divide each of the starting compents by 2 ... | |
| Work related problem | 5/17/2009 |
| Q: A person employs 45 workers to complete a project in 45 days. Only half of the project was ... A: Since they took up 2/3 of the time to complete half the project, this means that they only have 1/3 ... | |
| Coin probabilites of a spun coin and on edge | 5/16/2009 |
| Q: I saw a video lecture on mathematics (taught by reputable PhDs) and they said that a penny spun will ... A: There was probably something else in the discussion. The chances of a head and a tail are both ... | |
| math | 5/16/2009 |
| Q: Factor the trinomial: x^2-11x+18 A: tri- refers to 3. The highest power of x is 2, however, so I have heard them referred to as ... | |
| compound interest and simple interest | 5/16/2009 |
| Q: In Township K each property is taxed at 8% of its assessed value.If the assessed value of a property ... A: THere are two different approaches. A) This is an increase of $24,000 - $20,000 = $4,000. 8% is $8 ... | |
| consecitive odd integers | 5/16/2009 |
| Q: If the first and third of three consecutive odd integers are added, the result is 87 less than 5 ... A: The first number is n. The second number, then, is n+2. The third number is n+4. What we want is (n ... | |
| math | 5/15/2009 |
| Q: By using the Factor Theorem, find the prime factors of the polynomial. x^3-x^2-17x-15 A: First try: (x+1) 1 1 into 1 -1 -17 -15: First multiplier: 1, so 1 1. Result 0 -2 -17 -15. Second ... | |
| alegebra | 5/14/2009 |
| Q: i can't seem to get this right. HELP!!! Simplify (2x+3)(x-4)=? if you know the answer and show me ... A: The function is really each part of the first set of paraenthesis times each part in the second set ... | |
| Business Math | 5/14/2009 |
| Q: The profit in (thousands of dollars)for a company spending an amount X (in thousands of dollars) in ... A: a) Take the derivative: P'(x) = -3x²/10 + 12x. Set it equal to 0: -3x²/10 + 12x = 0. Find the ... | |
| trignometry | 5/14/2009 |
| Q: a tree 12 meter high is broken by the wind in such a way that its top tuches the ground and makes an ... A: The tree falls in such a way to make a 60° angle with the ground. That means the angle where the ... | |
| math | 5/14/2009 |
| Q: Divide 3a^4-a^3b-15a^2b^2+11ab^3-2b^4 by a^2+2ab-b^2. A: Divide a^2+2ab-b^2 into 3a^4-a^3b-15a^2b^2+11ab^3-2b^4 by comparing the first terms. It can be seen ... | |
| math | 5/14/2009 |
| Q: Remove the parentheses and then combine the like terms in the following expression: ... A: To remove the parenthesis and combine terms gives 3a + 2b - 2a --b + 4a - 3b = 3a + 2b - 2a + b + 4a ... | |
| Probability | 5/13/2009 |
| Q: Suppose you draw 7 cards from a 52 card deck. What is the probability that the 7 cards include 3 ... A: This problem involves C(A,B). That is C(A,B) = A!/(B!(A-B)!). An example is say A was 5 and B was ... | |
| A bit of an unusual question ... | 5/13/2009 |
| Q: A bit of background (with apologies for the length) - When I was younger I was lucky (unlucky?) ... A: I forgot to attach that note with the math tables on it, so I guess I'll paste them in here, though ... | |
| Math | 5/13/2009 |
| Q: (x^-5x+8)(x^+1)= A: I will assume the x^ was for x^2. This means the problem is (x^2 - 5x + 8)(x^2 + 1). If (x^2 - 5x + ... | |
| probability | 5/11/2009 |
| Q: I need a definition of complex events for a 6th grade student. A: The definition of complex events is when there is something you need to know and there is data you ... | |
| continue complex number root | 5/11/2009 |
| Q: uhm i think i was not cleat but i know all about the Pythagorean thing and the 0-90(x,y) / 90-180 ... A: To compute the root of a complex number, it is easy to do in polar coordinates. In x-y coordinates, ... | |
| root of complex | 5/11/2009 |
| Q: Can you remind how to take the root of a complex number i will post what i know and you correct me ... A: Suppose that the start is the origin. Also suppose it's in the center of an open field. Set the ... | |
| On & Per Definition | 5/11/2009 |
| Q: From the following, is "...on $1.00..." and "...on $1000.00" the same as ...per $1.00 and ...per ... A: It was unclear to me exactly what was written, but I did my best at understanding it. If the ... | |
| Calculus Textbooks for Self-Study | 5/11/2009 |
| Q: I'm in grade eight and I've been self-studying for the past six months. I'm finishing up ... A: Contents of this Letter: 1) Need to Know 2) What you'll learn 3) The Book 1) Need to Know: I don't ... | |
| time and speed | 5/10/2009 |
| Q: A, B and C run around a circular track starting from the same point simultaneously and in the same ... A: Let's just look at minutes. There's is a more elegant way to solve this equation, but it won't take ... | |
| Pre Calc | 5/10/2009 |
| Q: Using the quadratric formula or complete the square to find all solutions for z in the equation: z ... A: I don't see what the quadratic equation has to do with this problem. Move everything that is not z ... | |
| root of complex | 5/9/2009 |
| Q: Can you remind how to take the root of a complex number i will post what i know and you correct me ... A: Converting to polar coordinates is the easiest way to compute roots of complex numbers. It is much ... | |
| Primes | 5/9/2009 |
| Q: How do you prove: 2n+1 and n+1 are relatively prime? ANSWER: The only common factor between 2n+1 ... A: I was thinking about it for awhile and it made sense to consider n as even and as odd in the way I ... | |
| root of complex | 5/9/2009 |
| Q: Can you remind how to take the root of a complex number i will post what i know and you correct me ... A: To start with, when (a + bi) is squared, you get a² + 2abi - b². This means that 5 = a² - b² ( not ... | |
| Primes | 5/8/2009 |
| Q: How do you prove: 2n+1 and n+1 are relatively prime? ANSWER: The only common factor between 2n+1 ... A: If k were 4, that would make the second number 9. The first number, though, is said to be 4k+1. That ... | |
| Binomial Probability | 5/7/2009 |
| Q: Assume that 13% of people are left-handed. If we select 5 people at random, find the probability of ... A: a) The first left is fifth means the first four were right handed. The chance of being right handed ... | |
| function of sets | 5/6/2009 |
| Q: Would you proof the following for me? This is a long one and I believe I got it correct but I would ... A: I'm thinking about that one... and thinking ... and ... | |
| time and work | 5/6/2009 |
| Q: A water tank of 1000 liters capacity is connected to a tap, which can fill at the rate of of 20 ... A: The tank is 1000 liters. It was filled at 20 liters per minute. It was let fill for 1 hour. Now 1 ... | |
| circle equation | 5/6/2009 |
| Q: i have a problem with figuring out the equation of a circle that (3,0) - (6,9) - (9,-3) are on it ... A: OK, I will do it over, since I don't think what I did was even right. I mean, it had the right ... | |
| Which parametric test shall I use for a hypothesis test? | 5/5/2009 |
| Q: This is question is for statistics. Here it is: The following data represents the ages of drivers ... A: I would divide the data into intervals. I'm not sure how many years there are or how many eruptions ... | |
| maths | 5/5/2009 |
| Q: 1.find the determinant of the following 5x5 matrix 4 1 8 2 5 1 0 0 3 1 4 2 3 1 3 6 4 4 1 0 7 3 1 2 ... A: 1. When the dice are the same, both of them have the maximum number. The only way a maximum of 1 is ... | |
| proof of primes | 5/5/2009 |
| Q: Could you assist me in proving the following? Prove or Disprove: P is greater or equal to 5 is a ... A: Start by assuming all numbers to be prime (we both know they're not, but just do it anyway). The ... | |
| function rules that relate to r and t | 5/4/2009 |
| Q: input r 1 2 3 4 output t 11 25 39 53 A: Look at the difference in the input. Between any two adjacent numbers, it is always 1. Look at the ... | |
| Proof by contradiction | 5/4/2009 |
| Q: I have a question for proofs: If a and n are natural numbers and a is greater than or equal to 2 ... A: If a is an even number, then a² is an even number. If a² is an even number, then a²+1 is an odd ... | |
| Trig | 5/4/2009 |
| Q: Verify [cot(x)^2][cos(x)^2] = cot(x)^2-cos(x)^2 A: Take the right side. Note that cot(x) = cos(x)/sin(x). The right side is then cos²(x)/sin²(x) - ... | |
| probability | 5/4/2009 |
| Q: Using two six sided dice, numbered 0,2,4,6,8,10, any roll 10 and over gets a second roll, and if the ... A: You probably have the answer, but here's my insight into the problem. I believe I got it right this ... | |
| sines math problem | 5/4/2009 |
| Q: Use the Law of Sines to find the measure of angle B (to the nearest tenth). If there is moe than one ... A: The law of sines for a triangle says that SinA/a = SinB/b. In this case, we have Sin(29°)/25 = ... | |
| Primes | 5/4/2009 |
| Q: How do you prove: 2n+1 and n+1 are relatively prime? A: The only common factor between 2n+1 and n+1 is 1, therefore they are relatively prime. If the ... | |
| proof of primes | 5/4/2009 |
| Q: Could you assist me in proving the following? Prove or Disprove: P is greater or equal to 5 is a ... A: The possible list of all numbers that are greater than 5: 6n, 6n + 1, 6n + 2, 6n + 3, 6n + 4, and 6n ... | |
| Simple Statistic Question | 5/3/2009 |
| Q: I would like to ask you a few basic questions on statistic about normal distribution. I'm currently ... A: A good way to do it would be to say that it is from a normal that goes from 10 to 20 and for the ... | |
| stats | 5/1/2009 |
| Q: we got a review to for a final and i dont understand how to do this problem. If you could help me ... A: We are given µ = 25,000 and σ = 3,500. It looks like the point of interest is 2,500. For 100 ... | |
| Probability | 5/1/2009 |
| Q: Given a mean of 30inches a standard deviation of 2.5 inches, If you sample 100 people what is the ... A: Take 2.5² and you get 6.25 . Dividy by 100 and get 0.0625 . Take the squareroot and get 0.25 . Of ... | |
| Brain Teaser Math | 5/1/2009 |
| Q: My 5th grade daughter comes home with a weekly brain teaser for her advanced math class. This ... A: These are: 28,96,48,60,12 These are Not: 300,90,26,47, 50 Then which of these are? ... | |
| math...please help | 4/30/2009 |
| Q: 7. The acceleration of an object varies directly as the force acting on it. If a force of 240 ... A: 7 Q: 240 => 150 m/s²; 100? The answer would be to divie by 240 and multiply by 100. In other words, ... | |
| Integrals | 4/30/2009 |
| Q: i have tried and tried with this one, civil engineering yr1 :-D square root (4 + x^2) any help ... A: You mean ⌠ ⌡ (4+x²) dx ? Use a triangle with far side x and near side 2, angle Θ. ... | |
| allgebra | 4/30/2009 |
| Q: (x-7)=5(x-3), hey soorow to bother you again i find allgebra simply confusing. i came clear for the ... A: We know that x - 7 = 5(x-3). Multiply out to drop the brackets on the right. That gives x - 7 = 5x ... | |
| Precalculus | 4/30/2009 |
| Q: cot 3.14592654/12 A: The cot() is known to be 1/tan(). The number you have is a little bigger than π, so it is ... | |
| algebra | 4/30/2009 |
| Q: i get confused, 2x+5/4=3-x, would really appreicate the help thankyou A: I take it that is really (2x+5)/4 = 3-x. To solve problems like this, do the following: 1 eliminate ... | |
| Verify the Identity | 4/30/2009 |
| Q: verify this identity -sin2x+sin6x/sin2x-sin6x= tan4x cot2x A: Let u = 2x. That gives you (-sinu + sin3u)/(sinu - sin3u) = tan2u cotu. Note that tan2u = ... | |
| numbers again with last mail | 4/30/2009 |
| Q: The expert can't answer your question. Your Question was: w,x y,z are integers or zero a,b,c are ... A: Someone suggested that if you take the sum of a_i to the n, i needs to go from 1 to n. In other ... | |
| Problem | 4/29/2009 |
| Q: 1.In the xy-plane, the solution set to (24/y) > (10/x) > (120/xy) splits up naturally into four ... A: The answer to 1 was so long I almost forgot about 2, but here it is. 2.Find the eigenvalues of a ... | |
| pre calc | 4/29/2009 |
| Q: 1. How does the graph of f(x)= -x^2+1 compare to that of g(x)= x^2 ? 2. Use long division to divide ... A: 1. The first is a parabola opening down and centered at x=0. The second is a parabola opening up and ... | |
| right triangle | 4/29/2009 |
| Q: Solve the right triangle (to the nearest tenth) given B=15degrees, and b=30m. B is not the ... A: The tan(15°) is 2-√3. We know that b/a = tan(15°), so a can be found. This is a right ... | |
| integration | 4/29/2009 |
| Q: Sir: Good day! thanks for your reply. you need to see more of the problem to solve it. here's the ... A: Did I forget the attatchment to the answer? Well, I can't attach it now, so here it is in a bad ... | |
| this is regarding algebra | 4/29/2009 |
| Q: sir, what is the physical meaning of a matrix ? please explain me with a scientific example. ... A: I'll give a planar vector space and a cubic vector space. Planar If a football field were a vector ... | |
| Dimensions | 4/29/2009 |
| Q: A bookcase is to be constructed with 4 shelves. Height- 3 feet more than the width. Amount of wood ... A: Height H equals widht W + 3, so H = W + 3. Total wood = 30. The boards used for shelving are 3W, or ... | |
| quadriatic word problem | 4/28/2009 |
| Q: Question 1: one rocket has an initial velocity of 48 feet per second and the other one has an ... A: If a -16 is factored out of -16t + 64, the answer is -16(t-4) = 0, so t = 4. If a -16 is factored ... | |
| quadriatic word problem | 4/28/2009 |
| Q: Question 1: one rocket has an initial velocity of 48 feet per second and the other one has an ... A: The two equations to solve are -16t² + 48t = 0 and -16t²+64t = 0. Two find the maximum height, set ... | |
| Continuous functions | 4/28/2009 |
| Q: am struggling to get a start on thisLet functions f(x) and g(x) be continuous at x = a, with g(a) ... A: (i) If g(x) is negative, say g(x) = -5, then g(a) -5. There is no value anywhere such that g(x) > ... | |
| this is regarding algebra | 4/28/2009 |
| Q: sir, what is the physical meaning of a matrix ? please explain me with a scientific example. A: Suppose you have 3 equations, 3 unknowns. They were the following: 2x + 3y + 5z = 43 5x + 2y - 4z = ... | |
| Prime numbers | 4/27/2009 |
| Q: Why isn't "1" considered a prime number? According to wikipedia the numbers that are multiplied ... A: To say it now, 1 is not considered a prime number. Let us calculate the squareroot of 77284. First, ... | |
| probability | 4/27/2009 |
| Q: Using two six sided dice, numbered 0,2,4,6,8,10, any roll 10 and over gets a second roll, and if the ... A: The first sums are OK. 0: 1/36 2: 2/36 4: 3/36 6: 4/36 8: 5/36 10: 6/36, but you also need to know ... | |
| Cluster/density analysis | 4/27/2009 |
| Q: I'm interested in finding a general way to solve this problem: I have some 2-dimensional data ... A: I would graph the points and look at how it looks. Look for an area that has the most points ... | |
| Algebra Question | 4/26/2009 |
| Q: I am stuck on how to start this question??? For f:[a,b] -> [a,b] continuous, show for some x E ... A: Suppose this were not the case. That is, for some x in [a,b], f(x) != x. Choose the right x1 and x2 ... | |
| one sample | 4/26/2009 |
| Q: A local politician running for reelection claims the mean prison time for car thieves is at least ... A: I believe the claim of the politician is Ho. That is, they serve at least 4 years. That would mean ... | |
| Prime numbers | 4/25/2009 |
| Q: Why isn't "1" considered a prime number? According to wikipedia the numbers that are multiplied ... A: You hit on a hot topic of mine. As I learned it, the best way to describe prime numbers is that ... | |
| Plz answer these questions | 4/25/2009 |
| Q: - 1) Discuss the principles of modelling in Operations Research. Identify the application of O.R. in ... A: 1. Operations research assumes that each item has a cost per unit. It assumes the cost is linear. ... | |
| pre-calc | 4/24/2009 |
| Q: 1. find the remainder when f(x)=x^3+x^2+x+2 is diveded by (x-4) 2. f(x)=x^2-9/x-3 and g(x)=x-9/x-3 ... A: 1. The divisor is 1 -4 and what to divide into to is 1 1 1 2. Each time, make the leading term in 1 ... | |
| finance | 4/24/2009 |
| Q: A company find that it can operate in either of two modes: 1. Fixed Costs of $100,000/yr with ... A: Since all of the variables are in $, per year, and units, I won't put in the notation, but just the ... | |
| Advanced Calculus | 4/24/2009 |
| Q: The Taylor polynomial of degree 2 generated by a twice differentiable function f(x) at x=a is called ... A: Let x0 be 'x naught'. a) The answer is f(x) = f(x0) + (x-x0)f'(x0). b) f(x) = f(x0) + (x-x0)f'(x0) ... | |
| pre-cal vectors | 4/24/2009 |
| Q: An airplane has an air speed of 550 miles per hour bearing North 30 degrees West. The wind velocity ... A: On this problem, I'll state the rounded numbers. The actual number is several more digits in my ... | |
| math!!! | 4/23/2009 |
| Q: i am a university student in malaysia n this got the better of me. 61a - 40b - 50c = 0..... (i) 93a ... A: See attached sheet. For the first column, that's the factors I used. The second column is for A, the ... | |
| divisor | 4/23/2009 |
| Q: 1. Find the number of the positive integral divisors of 72^72. 2. Find the sum of the positive ... A: 1. Is that 72 to the 72nd power? There are 2 unique prime factors – 2 and 3. The number 72 has ... | |
| geom2 | 4/23/2009 |
| Q: 4. In equilatral triangle ABC with side 3, D and E are points on AB and AC, respectively, such that ... A: AD = ED = 2 means AD is 4. It is an equilateral triangle, so all of the other sides are 4. Also, ... | |
| maximum | 4/23/2009 |
| Q: find the maximum value of 4(x^2+x+2)/(x^2+x+5)(x^2+x+1) pls show your solution thnxxx... i let a = ... A: We know that f(x) = 4(x^2+x+2)/(x^2+x+5)(x^2+x+1). y =4(a+2)/((a+5)(a+1)) where a = x²+x, so for ... | |
| Probability of good sex | 4/22/2009 |
| Q: So I have been married for 28 years. My wife, who has regular menstrual periods varying between 20 ... A: I'll assume it takes 3 days for a period. I'm not real sure, but it sounds safe. The number of days ... | |
| Demand Equation with Profit Maximization | 4/22/2009 |
| Q: I need some help with the following question please: A manufacturer can produce at most 120 ... A: I'be been working on it. I can see that P(q) = q^2 - 100q + 3200 and C(q) = 2/3q^2 - 40q +10000/q. ... | |
| transformation | 4/22/2009 |
| Q: Sir: Good day! thanks for your reply. you need to see more of the problem to solve it. here's the ... A: p(x,z) = exp(-x-z), x>0, z>0. Let u=(x+z)/2, w=(x-z). q(u,w)=exp(-2u), u>|w/2|. Yes, I see how ... | |
| Derivatives of other basic functions | 4/21/2009 |
| Q: Find dy/dx: 1) x2^y+y2^x=4 2) x=√(1+e^2y ) A: 1) It looks like x times 2 to the y + y times 2 to the x. Is this right? The derivative would be ... | |
| intermediate algebra | 4/21/2009 |
| Q: I have a problem with a question on a homework assignment. the question states to perform the ... A: Do the way this program translates, I'm not sure if I get the question exactly. Is it 2x²/10 - 4x - ... | |
| math | 4/21/2009 |
| Q: Hey Mr. Wilson, I'm very confused and i don't know how to answer this Maximum and minimum problem. A ... A: The gutter is 8 m long and 24 cm wide. This would give it a height h and a width 24-2h. Note that ... | |
| pre-calculus | 4/21/2009 |
| Q: over a 28 day period, the cost per litre of petrol is modelled by C(t)= 9.2sinpi/7(t-4)+ 107.8 ... A: Let us look at the sin wave. It oscillates between -1 and 1, so the oscillation is 2. It oscillates ... | |
| PLEASE HELP ME ASAP!!!!!!! | 4/20/2009 |
| Q: Can you please help me solve these Trig Identities: [sin^2(A)/tan^2] + sin^2(A) [csc(A)/cos(A)] + ... A: sin²A/tan²A + sin²A tanA is sinA/cosA, so tan²A is sin²A/cos²A. Since we have 1/tan²A, the value to ... | |
| Trigonometry | 4/20/2009 |
| Q: Show that (sin 2a)/(1-cos 2a)=cot a. Using sin 2a & cos 2a formulae. Many Thanks A: We know that sin 2a = 2 sina cosa and that cos 2a = 2 cos²a - 1. That makes the formula ... | |
| Differentiation 2 | 4/20/2009 |
| Q: The curve y=e^x/(cosx),for -.5x(pi)<x<.5(pi),has 1 stationary point.Find the x-coordinate of this ... A: x was taken from -0.9π/2 to 0.9π/2 by π/10 and put it into the function given. I ... | |
| Logarithms equation | 4/20/2009 |
| Q: Solve the equation ln(x+2)=2+ln x,giving your answer correct to 3 decimal places. Thanks a lot A: Note that we can say that lnx = ln(x+2) - 2. Take the exponent on both sides. Since e^ln(x) = x, we ... | |
| population | 4/20/2009 |
| Q: The current population of a population of a particular town is 10 000 and it increases at the rate ... A: The number 50,000 is known as P(t) in t years. Put that in the equation and get 50,000 = ... | |
| Writing numbers | 4/20/2009 |
| Q: My husband and I are right now doing a trivia game with our neighbors where they gave us a bunch of ... A: One thousnad = 10^3 = 1,000. One million = 10^6 = 1,000,000. One billion = 10^9 = 1,000,000,000. One ... | |
| Proving Trig Identities | 4/19/2009 |
| Q: "all x's stand for theta (1+sinx)(1-sinx)(secx+1)(secx+1) [sinx-(sinx)(cosx)]/1-cosx ... A: Now I usually don't do this many, but sometimes I do. Apparenlty you got lucky for some reason. ... | |
| maths | 4/19/2009 |
| Q: simplify:- [tan^-1(1/2)]+[tan^-1(1/8)]+[tan^-1(1/18)]+______+infinity ANSWER: Aha! I think I got ... A: First part: If the tangent is 2/3, that means the far side could be 2 and then the near side would ... | |
| poisson distribution | 4/19/2009 |
| Q: A book contains 500 pages. If there are 200 typing errors randomly distributed through out the book. ... A: 200/500 = 0.4. The Poisson distribution is (0.4^k)(e^-0.4)/k!. a) Errors=5 Exactly 5 errors would ... | |
| pre-cal - verifying identities | 4/19/2009 |
| Q: Please help - think I got this one but need to be sure 1 + sin x = cos x / (sec x - tan x) Thanks ... A: I don't worry about the space. I assume sinx is sin x, cosx, secx is sec x and tanx is tanx. I ... | |
| maths | 4/18/2009 |
| Q: simplify:- [tan^-1(1/2)]+[tan^-1(1/8)]+[tan^-1(1/18)]+______+infinity A: Aha! I think I got it. The bottom goes 2, 8, 18, ... That is 2*1², 2*2², 2*3², etc. So the next ... | |
| Proving Identities | 4/18/2009 |
| Q: I have to prove the following identity... (sec^4x - 1)/ tan^2x = 2 + tan^2x A: Let s = secx, t = tanx. The equation is (s^4 - 1)/t². Factoring the to gives (s²+1)(s²-1). Since ... | |
| Derivatives of other basic functions | 4/17/2009 |
| Q: Find the derivative of y y= (e^(-x)+ sin2x)/(e^(-x)- cos3x) A: This is a long and complicated problem. Do to its length, I may have made an error, so check ... | |
| Permutations and Combinations | 4/17/2009 |
| Q: Find 'n', if 6(nC7) = nP7 A: If the order doesn't matter, it is a Combination. If the order does matter it is a Permutation. ... | |
| inverse functions | 4/17/2009 |
| Q: Find the inverse of each function and state whether the inverse is a function 1. F(x) = x^3 - 4 2. ... A: To invert a function, it must be 1-to-1. The first function is. Let y = x³ - 4. We can say that x³ = ... | |
| Pre-Cal/Trig | 4/17/2009 |
| Q: Dealing with simple harmonic motion: How do you graph the vertical position of the sphere as a ... A: I'm not sure I get how big this sphere is. I will assume the center is at (0,0) so the radius is 10. ... | |
| proof | 4/16/2009 |
| Q: Let f:X→Y and g:X→Y be functions such that g,f is one-to-one. Does one of f,g need to ... A: As I understand it, f takes X->Y and g takes X-.Y. It then says both functions are 1-to-1. If Y is ... | |
| proof | 4/16/2009 |
| Q: Prove or disprove that (P(n,r))/n=P(n-1,r-1) I don't know what i am doing on this, please help! A: P(n,r) = n!/(r!(n-r)!). P(n-1,r-1) = (n-1)!/((r-1)!(n-r)!). Lets look at these two. One has an n, ... | |
| equations | 4/16/2009 |
| Q: Solve |2x - 4| < 10 - A: To solve an equation with |2x-4| in it, not when | | is negative and when | | is positive. The best ... | |
| Algebra 2 | 4/16/2009 |
| Q: The height h in feet of a person on a waterslide is modeled by the function h(t)=-0.025t^2 - ... A: To solve this algebra problem, drop the decimals first by multiplying by N/N where N is the right ... | |
| infinite geometric series | 4/15/2009 |
| Q: How do you figure out the sum of an infinite series? for example if the problem is : an infinite ... A: The series is the Σa^n, n = 0 to ∞. If |a| < 1, this is known to be 1/(1-a). The a here ... | |
| Trigonometry Projectile Motion | 4/15/2009 |
| Q: Please help me solve and understand how to solve this Trigonomety Projectile Motion Word Problem. ... A: On the ctn(Θ) = 2x/2y + gt², I don't understand where it comes from. I also don't know if it is ... | |
| Math Problems | 4/15/2009 |
| Q: A bag of potatoes weighing 5 pounds and 12 ounces costs $2.07. What is the cost of 1 pound of ... A: This isn't the answer all worked out for each problem, but it does tell you how to do them. ... | |
| Math and Algebra Problems | 4/15/2009 |
| Q: If your taxable income is from $4,000.00-$7,499.00 your is $100 plus 5% of any amount $4,500.00. ... A: I'm not sure I follow what you're asking. It looks like the tax is 5% on anything between 4,000 and ... | |
| algebra | 4/15/2009 |
| Q: i=prt jack has earned a bonus of $20,000 at work. he invested this $20,000 into one investment that ... A: Let x be the amount invested at 4%. This would mean he got 0.04x interest out of that account. This ... | |
| equations of lines and planes | 4/14/2009 |
| Q: 1). find the equation of the plane through the line (x+1)/2=(y-1)/-1=(z-2)/3 and parallel to the ... A: I don't know if I remember the facts about planes, but I'll give it a try. The plane would be z = ... | |
| algebra 2 asymptotes | 4/13/2009 |
| Q: What is the horizontal asymptote for x-5/x+1 ??? A: If the equation is really (x-5)/(x+1), the horizontal assymptote is the horizontal line that the ... | |
| trig | 4/13/2009 |
| Q: in which quadrant is the terminal side of the angle [theta] [theta]=-225degrees and why A: There are four quadrants. Each quadrant contains 90 degrees. The first quadrandt is 0 through 90. ... | |
| solving equation | 4/13/2009 |
| Q: how to solve this equation and get value of a: 1.4544*10^-4 a^3.5 - 1.996498184*10^7 a^2 - ... A: I used a spreadsheet to find where to look for a root. In row 1 are the numbers. In row 2 are the ... | |
| composite functions | 4/13/2009 |
| Q: f(x) = lnx and g(x) = cosx Find the composite functions f(g(x)) and g(f(x)) and give their domains. ... A: The formula f(g(x)) would be the result of putting g(x) in for the x in f(x). Since f(x) = ln(x) ... | |
| More probability... | 4/11/2009 |
| Q: Have another that is stumping me in getting the right "formula". From a standard deck of 52 cards, ... A: Every now and then I make a silly mistake, and this was one of them. I was think a full house was 3 ... | |
| Operations Research | 4/11/2009 |
| Q: Kindly help in solving the question attached. Thanking You in advance. Regards, satish A: Invert ----------------------- Solve this problem as a dual problem. Rotate the problem by 90 ... | |
| More probability... | 4/11/2009 |
| Q: Have another that is stumping me in getting the right "formula". From a standard deck of 52 cards, ... A: A Hand ------- Using the same approach, the number of total ways of drawing a hand is choosing 5 ... | |
| Probability | 4/11/2009 |
| Q: A test consists of 25 True/False questions. Assume each question is randomly answered. a)How many ... A: a) There are 25 questions with two choies each, so the answer is 2^25, which is 33,554,432. 80% is ... | |
| Average Compound Interest | 4/10/2009 |
| Q: How is the average determined for the following amount if it earns compound interest? Here are my ... A: By looking at the problem, we can see that 1.05 and 0.98 are almost one, so the answer should be ... | |
| Probability of success for a test | 4/10/2009 |
| Q: A test bank in the public domain consists of 500 questions. A random selection of 60 questions is ... A: 500 number of questions 60 number on a test 0.7 percent needed 1.28 standard ... | |
| Average Compound Interest | 4/10/2009 |
| Q: How is the average determined for the following amount if it earns compound interest? Here are my ... A: To add 5 percent, the starting number is multiplied by 1.05. To subtract 2%, note that if we ... | |
| Statistics | 4/9/2009 |
| Q: I'm having lot of problem solving this problem, but I tried similar problems and I got some of them ... A: That would be 1 - P(x<4), = 1 - P(x=0) - P(x=1) - P(x=2) - P(x=3). Let C(A,B) be A choose B = ... | |
| GCD | 4/9/2009 |
| Q: 3. The numbers in the sequence: 101 , 104 , 109 , 116 , ... are of the form asubn = 100 + n^2 , ... A: Tow numbers that are squared have the same divisors as the number itself, but twice as many of each. ... | |
| Parabola Reflection Query | 4/9/2009 |
| Q: In the form y=a(x-p)^2+q, would it be possible to reflect along the x-axis(Not at the y=0, but where ... A: The three values in the equation are a, p, and q. When x=9, the graph is at a miniumum if a is ... | |
| A very intriguing expression | 4/9/2009 |
| Q: As a dedicated math student, I often make up my own problems and solve them for fun. One day, I ... A: The first term is simple enough - it's 1. The second term is also simple enough - it's 1+√2. ... | |
| Proof sets | 4/8/2009 |
| Q: I am currently working on a proof that is killing me! I can't figure out where to go next. The proof ... A: Actually, this won't allow me to send a .bmp file, so I changed it to a .JPG file; not that you ... | |
| Trig | 4/7/2009 |
| Q: Verify that (sinx-cosx)²=1-2sinxcosx is an identity. A: On the right side, use the identity 1 = sin^2x + cos^2x. This will give you sin^2x + cos^2x - ... | |
| proving trigonometry | 4/7/2009 |
| Q: proving ..tq sin^4(a)+cos^4(a)=1-2sin^2(a)cos^2(a) A: Take the left side and add and subtract 2sin^2(a)cos^2(a) from it. The result would be sin^4(a) + ... | |
| Determinants | 4/7/2009 |
| Q: I'm a 25 year old computer science student. There's a question regarding determinants that I've been ... A: Consider putting this matrix in upper triangular form so that the determinant is the product of all ... | |
| Statistics | 4/6/2009 |
| Q: I have developed a simulation that models a complex process. The simulation has been verified and ... A: I would use the binomial and continue gathering data on whatever the product is being soold. Mark ... | |
| Trig | 4/5/2009 |
| Q: A Little League baseball diamond has four bases forming a square whose side measure 60 feet each. ... A: A Little League baseball diamond has four bases forming a square whose sides between the bases ... | |
| hi | 4/5/2009 |
| Q: A 200 foot tower on the side of a hill that form a 5 degree angle with the horizontal. Find the ... A: A Little League baseball diamond has four bases forming a square whose sides between the bases ... | |
| Cumulative frequency | 4/5/2009 |
| Q: I have been given the first runner to finish took 54 mins and 2000 runners took part and given table ... A: We are going to approximate with a normal distribution. Assume that there will be 1,000 above the ... | |
| Statistics-mean | 4/5/2009 |
| Q: Estimate the proportion of commuters whose travelling times are within 1 standard deviation of the ... A: I would use the normal table. Data all about the normal distribution is found in ... | |
| Data representation | 4/5/2009 |
| Q: Grouping the data with classes 10-19,20-29,...,60-69,determine the frequencies for these classes & ... A: Yes, that means it wants you to draw a histogram. I find it best to input 10 to 19, 20 to 29, 30 to ... | |
| Stastics | 4/5/2009 |
| Q: In the question given the results represented by stem-and-leave diagram. I dont understand the ... A: Usually when the problem asks for percentages to be shown, it is best to use a pie chart. If your ... | |
| Injection | 4/4/2009 |
| Q: I have a question concerning one-to-one functions, otherwise known as injections: Let a, b, c, and ... A: If we take f = (ax+b)/(cx+d) and solve for x, the first thing is to multiply both sides by cx+d and ... | |
| analysis | 4/3/2009 |
| Q: 1. Let f be integrable on (-infty,+infty). Suppose a function F is defined by F(x)=integral from ... A: 1. Since the derivative is the opposite of the integral, anything that can be integrated can ... | |
| decimal | 4/3/2009 |
| Q: if (sqrt2 + sqrt3)^2008 is represented as decimal notation. what is the first two digit after ... A: I don't know of any technology that can do that man places. There might be some cute trick someone ... | |
| Pre-Cal Trigonometric Identities | 4/1/2009 |
| Q: I have question about simplifying trig identities. How do i simplify sin(theta)(Csc B - Sin B) and ... A: Now if the angles are suppose to be the same in the first one: Is that first one suppose to be ... | |
| Solve for r in monthy compound interest formula | 4/1/2009 |
| Q: I have a math problem that I am having trouble with and my textbook doesn't really explain it very ... A: The equation you have, 3586.58 = 2000 ( 1 + r/12)^12(5), is what you need. It is really 3586.58 = ... | |
| maths | 4/1/2009 |
| Q: 4) In an experiment to determine which of three different missile systems is preferable, the ... A: The Kruskal-Wallis test determines the rank of each variable. Put all of the numbers in order. ... | |
| Problem set in summer class | 3/31/2009 |
| Q: 1.)mary is 24 years old.mary is twice as old as ana was when mary was as old as ana as now.how old ... A: 1) If Mary is twice as old, she has lived as long after Ana’s birth as before. That means that when ... | |
| probability | 3/31/2009 |
| Q: Sir i want to know an appropriate site or ebook for probability Am very week in this The topics are ... A: In probability, if A and B are independent events, u is used for the union and n is used for the ... | |
| Pre Calc | 3/31/2009 |
| Q: I need to find the exact value of this equation. I'm not quite sure how to go about with it. the ... A: That looks like 45 degrees split into 20 and 25. From trigonometry, I remember that tan(A+B) = ... | |
| problem solving | 3/30/2009 |
| Q: 1. For which integers k, if any, is x^2+k a factor of x^4-3x^3+6x^2-3xk+8? 2. A man began an ... A: 1. Look at it as dividing x²+k into x^4 - 3x^3 + 6x^2 - 3kx + 8. This, in long division form, is (1 ... | |
| polar to rectangular equation | 3/30/2009 |
| Q: r^2 = 8/(2 - sin^2(theta)) A: To convert polar to rectangular, we need to know that x² + y² = r² and y/x = tan(Θ). This ... | |
| circle | 3/28/2009 |
| Q: i m studying in 8th std. and i don't know how to measure the subtended arcs and cyclic ... A: Subtended Arc The subtended arc is how much of a circle. There are 360 degrees or 2pi radians in a ... | |
| quantitative analysis for managerial applications | 3/28/2009 |
| Q: Sir,I am MBA student. Please give the answers of my questions. Thank you. 1.Nonstandard dice can ... A: 1.Nonstandard dice can produce interesting distributions of outcomes. You have two balanced, ... | |
| right triangle trig | 3/27/2009 |
| Q: The height of a mountain peak is observed at a distance, where the angle of elevation is 30. 1215ft ... A: Make sure if you use a calculator, the angles are in degrees. The triangle has a 30 and 35 degree ... | |
| root of i | 3/26/2009 |
| Q: what is the root of the imaginary numers? A: When taking the squareroot of imaginary numbers, the complex plain is looked at with the real ... | |
| Verifying Identities | 3/25/2009 |
| Q: i have a quiz on it tomorrow and do not know how to do this stuff. Can you answer some of these ... A: That third problem took me awhile. sin²(x)/(sin(x)(1+cos(x)) + (1+cos(x))²/(sin(x)(1+cos(x)) = ... | |
| Pre-cal | 3/25/2009 |
| Q: Find the period and graph the function. 1. y = tan 2x 2. y = tan 1/2x 3. y = tan 5x 4. y = cot 4x 5. ... A: The tan(t) starts at 0 when t is 0. It goes up to ininity when t = pi/2. On the other side, it comes ... | |
| MATHS | 3/25/2009 |
| Q: Hey, I'm trying to figure out the answer to thisIf the displacement of a particle P at time t is ... A: Just as a reminder, note that exponets are taken care of before division. If I read it correctly, ... | |
| Maths problem | 3/25/2009 |
| Q: The area of a rectangle is 60 square meters. If each side is increased by 3 meters,the area of the ... A: If there is a rectangle, let's say that it is x by y. The area of the rectangle is 60, so xy = 60. ... | |
| QUANTITATIVE ANALYSIS FOR MANAGERIAL | 3/25/2009 |
| Q: 1.A study of iron deficiency among infants compared samples of infants following different feeding ... A: I found a papper that explains the difference between two means with differing standard deviations. ... | |
| Algebra | 3/24/2009 |
| Q: Ok I have been over this problem so many times it makes my head spin to even think about it. So here ... A: So is this the problem? √x = √(4 + 7√x). If so, square both sides, so x = ±(4 + ... | |
| finite math | 3/23/2009 |
| Q: How do I solve and graph these equations: A)5x=20 and 3x+2y=16 B) 3x+2y-16 and 3x-2y=16 A: A)5x=20 and 3x+2y=16 We can see that since 5x=20, x=4. Knowing this, we can put it into the second ... | |
| sin and cosine functions | 3/22/2009 |
| Q: could you please give me abrief explanation of the reason that sine is an odd function while cosine ... A: The definition of an even function is one that behaves like x^2n where n is an integer. x^2, x^4, ... | |
| pre-cal | 3/22/2009 |
| Q: what's the exact value of 4sin(2pi/3)cos(2pi/3)? do you just use the unit circle? A: I would remember that the sin() curve is 0 at 0, 1 at π/2, 0 at π, -1 at 3π/2, and 0 ... | |
| math | 3/20/2009 |
| Q: Integrate the following with respect to x. 3xsquared and, cos2x A: Integrating is the opposite of differentiating. Knowing this, we know the derivative of x^3 is 3x² ... | |
| maths | 3/20/2009 |
| Q: Differentiate the following with respect to x f(x)= 3sin x - 3ln x + 2 and, f(x)= 5xcubed + 2sin ... A: 1) The derivative of sin(x) is cos(x). The derivative of ln(x) is 1/x. Knowing this, the derivative ... | |
| triangles | 3/20/2009 |
| Q: Find the area of a triangle,ABC , given that the lengths AB = 8, BC =10, find and the angle ABC = ... A: I'm not sure exactly what this says, but I think its talking about a right triangle with sides 8 and ... | |
| Discrete maths | 3/20/2009 |
| Q: Show that (x+3) is a factor of the following cubic function, 2xcubed + xsquared - 13x + 6 = 0 Hence ... A: To show that (x+3) is a factor of 2x^3 + x^2 - 13x + 6, solve x+3=0 for x and see what happens. ... | |
| probability | 3/20/2009 |
| Q: I have n 6-sided dice. A 'hit' is a 5 or a 6 on a die. How do I calculate the probability of -at ... A: Peter 1. What I meant to say was the probability of a 5 was 1/6 and the probability of a 6 was 1/6. ... | |
| probability | 3/20/2009 |
| Q: I have n 6-sided dice. A 'hit' is a 5 or a 6 on a die. How do I calculate the probability of -at ... A: If a hit is a 5 or a 6 on a balanced 6 sided die, there is a 1/6 chance of getting a 5 and a 1/6 ... | |
| pre-cal | 3/20/2009 |
| Q: what are the steps needed to simplify cos(30+X)+cos(30-X)? please help i don't even know A: It is known that cos(A+B) = cos(A)cos(B) - sin(A)sin(B) and since cos(-X) = cos(X) and sin(X) = ... | |
| advance math | 3/19/2009 |
| Q: what is the phase shift and period in the equation y=-7sin(10x+5pi)=2? A: The phase shift on trig functions is how much is added on as a constant to the equation inside the ... | |
| maths problem | 3/19/2009 |
| Q: The sum of the squares of two numbers plus four times their product is equal to 382,the sum of their ... A: What you have is x and y. Now x² + y² + 4xy = 382 and x² + y² - 2xy = 4 can be used to say that 6xy ... | |
| Maclauren expansion | 3/18/2009 |
| Q: I have tried to work out the first 4 non zero terms of f(x) = sin^2x and then first 2 non zero of ... A: Yes, the one for sin²(x) is right. Now first derivative of sin²(x) is 2sin(x)cos(x). It becomes a ... | |
| algebra | 3/17/2009 |
| Q: we are suppose to factor the binomials completely 1. (2w+5)^2 - 1 2. (40x^7 - 1,715xy^3) ... A: 1. First, multiply it out. The answer would be 4w^2 + 20w +25 - 1, which would be 4w^2 + 20w + 24. ... | |
| Quantitaitve Analysis. | 3/17/2009 |
| Q: Plz help me in soving following questions...... A small accounting firm pays each of its five ... A: 1. A small accounting firm pays each of its five clerks Rs 25000, two junior accountants Rs 60000, ... | |
| math | 3/16/2009 |
| Q: What is the exponential notation of 108 and 420? Is the exponential notation for 70, 1? 144, 12 to ... A: When I use ^, I mean it as an exponet. Ex: 2^2 = 2*2 = 4; 2^3=2*2*2 = 8; 3^4 = 3*3*3*3 = 9*9 = 81. ... | |
| Probability | 3/16/2009 |
| Q: IN a market survey the following data regarding number of customers who prefer 3 brands of tea ... A: P(A) = 0.53, P(B) = 0.61, P(C) = 0.60. P(AnB) = 0.24, so P(AuB) = P(A) + P(B) - P(AnB) = 0.53 + 0.61 ... | |
| Problem | 3/15/2009 |
| Q: Use a double or half-angle formula to find the exact value of tan pi/12? I don't know how to do this ... A: One of the laws of trig is tan(Θ/2) = csc(Θ) - cot(Θ). This can be derived from the ... | |
| pipe problems | 3/15/2009 |
| Q: A pipe can fill up the tank with the drain pipe open in 3 hours. If the pipe runs with the drain ... A: If the drain is open, it takes 3 hours. If the drain is open for an hour, and then is closed, it ... | |
| Trigonometric Identities | 3/15/2009 |
| Q: Evaluate the ff: 1.) tan2A, given sin A = 3/5 and A Є QII 2.) sec 2x, given tan x = 5/3 and ... A: 1) To be in QII, we know that the adjacent side must be negative. Since the far side is 3 units and ... | |
| maths | 3/12/2009 |
| Q: a supermarket sells bottles of milk in 3 different sizes. 568ml bottles at 37p,2 litre botles ar 99p ... A: Is the p for pence? To find out, calculate the price per litre on each of them. The price on the ... | |
| Probability | 3/11/2009 |
| Q: I am having trouble with a question regarding probabilty and roulette. Here is the exactIf you make ... A: This game looks a little different than what I understand. The roulette wheel I know has 36 numbers ... | |
| Algebra and ordered pairs | 3/10/2009 |
| Q: I need help with these 2 problems: Decide whether or not the ordered pair is a solution of the ... A: (1) Put in x=3, y=5 and see if it is equal to 9. If it does, it is a solution. IF not, it's not a ... | |
| Confidence Intervals of a Triangular distribution | 3/9/2009 |
| Q: I am trying to find a way to quickly calculate confidence intervals using standard deviation in a ... A: Remember I had stated that we wanted to evaluate (ax - x^2/2)/a^2 to be equal to 0.90, 0.95, and ... | |
| Pre-Cal/Trig | 3/9/2009 |
| Q: Scott I'm having issue swith two problems in particular. I think, I always just loose my thinking in ... A: By the way, pie tastes really good. The term in math is the greek letter pi, which is ... | |
| Confidence Intervals of a Triangular distribution | 3/8/2009 |
| Q: I am trying to find a way to quickly calculate confidence intervals using standard deviation in a ... A: I will take the distribution to be b(a-|x|) for x between -a and a. To find out what b is, we need ... | |
| polynomial equation box problem | 3/7/2009 |
| Q: Open-top boxes are made by cutting equal squares from the corners of cardboard sheets that measure ... A: Since this is an algebra problem, I would think it would have a simple answer. Note that 32-x and ... | |
| trig | 3/6/2009 |
| Q: solve for x sec x + tan x = 1 A: I like to convert everything to sinx and cosx most of the time. secx = 1 / cosx and tanx = sinx / ... | |
| Statistics | 3/5/2009 |
| Q: Public works office knows that 80% of single family homes use natural gas. A consumer agency is ... A: The distribution is binomial with 80% success rate (chance that they use natural gas). A sample of ... | |
| Real Analysis Proofs | 3/3/2009 |
| Q: I have some proofs that I'm having trouble with and would greatly appreciate your help! 1) ... A: 1. If Bn is less than An and greater than Cn, and both An and Cn converge to some point, then when ... | |
| hi | 3/2/2009 |
| Q: how can I integrate an equation which is given in the form of (square root of A square- X square) A: If the problem is integrating root(sq(A) - sq(X)), then let theta be the angle Θ of a triangle ... | |
| Complex numbers in root of polynomial eqn | 3/1/2009 |
| Q: Consider the equation 2z^3-3z^2+18z+10=0.Given that 1-3i is a root of the equation and 1+3i is ... A: I put the equation in Excel. To do this, put -4 in A1 and 4 in A2. In A3, put =(A1+a2)/2. In cell ... | |
| complex numbers in modulus form | 3/1/2009 |
| Q: (i)Find the modulus & argument of each of the complex numbers z= (1+i)/(1-i) & ... A: For both variables, multiply by the conjugate of the denominator. That is, multiply the numerator ... | |
| weight and volume problem | 3/1/2009 |
| Q: Here is myImagine two spheres of metal, one nested concentrically inside the other. The outer sphere ... A: The volume of a sphere is 4πr³/3 where r is the radius. The variable r is d/(2π) where d ... | |
| trigonometry verifing identities | 3/1/2009 |
| Q: i need to verify each of the following identities. 1.sin x cos^3 x - cos x sin^3x = 1/4 sin4x 2. cos ... A: It uses the basic identities sin²x+cos²x=1, sin2x=2sinxcosx, sin(x+y) = sinx cosy siny cosx, and ... | |
| Stretching of polynomial function | 2/28/2009 |
| Q: I was wondering if it is possible to stretch a 4. degree polynomial function? If I have diagram with ... A: I'm not sure what you mean be stretch, but I'll take a crack at it. Take y=x². Picture it in your ... | |
| Beta function | 2/28/2009 |
| Q: I try to evaluate the following Beta function: f(t)= ∫ from 1 to 4 (x-1)^2(4-x)^3 dx. I have ... A: To change the value on the integrands, you have to change the variable. For example, the ∫(0 ... | |
| analytic trig question | 2/27/2009 |
| Q: sin a=40/41,-3pie/2 ,<a<-pie; tanB= square root-6, pie/2 <B<pie A: Note that pie is really pi. That's a greek letter. Pie is something that tastes yummy. Had any ... | |
| Precalculas | 2/27/2009 |
| Q: Solve over the given domain 1. sin x/sin x-1 = sin2x/sin x-3, Reals 2. csc2x=2,0< or = x < or = ... A: Note that sqrt is for square root and sq is for square. 1. sin2x = 2(sinx)cosx, so we can divide ... | |
| trigonometry verifing identities | 2/26/2009 |
| Q: i need to verify each of the following identities. 1.sin x cos^3 x - cos x sin^3x = 1/4 sin4x 2. cos ... A: The trig identities to use are sin²(x) + cos²(x) = 1 1 + ctn²(x) = csc²(x) 1 + tan²(x) = sec²(x) ... | |
| Set_Theory_and_Logic | 2/26/2009 |
| Q: Is there any sense in defining the logical conditions such as "sufficient reason" and "necessary ... A: I'm not sure about the difference between "sufficient reason" and "necessary reason" for something, ... | |
| Probability | 2/26/2009 |
| Q: Mary plans to give 5 strings of beads for each of her 8 guests. She buys 20 purple strings, 10 ... A: There is a total of 20+10+10=N strings. The probablility of a purple is 20/N. The probabilitiy of a ... | |
| rth grade geometry | 2/25/2009 |
| Q: If cylinder has 28cm diameter, how many cm will water level drop if 1 liter is removed? (Height is ... A: The diameter is 28 cm, so the radius is 14 cm. The area is then πr², or 14²π cm, which is ... | |
| Beta function | 2/25/2009 |
| Q: I try to evaluate the following Beta function: f(t)= ∫ from 1 to 4 (x-1)^2(4-x)^3 dx. I have ... A: The only way I know to do this is to multiply it out. (x-1)²=x²-2x+1. (4-x)^3 = 64 - 48x + 12x^2 - ... | |
| Word Problems | 2/25/2009 |
| Q: A paint supplier has two machines that produce both indoor and outdoor paint. To meet one ... A: Facts We need 60 gallons of indoor paint and 100 gallons of outdoor paint MI) Produces 3 indoor, ... | |
| Basic Algebra | 2/25/2009 |
| Q: What would the formula be for expressing a 2% yearly rate of increase on a monthly rent over a 15 ... A: You get the basic amount of 1 plus 2%, which is 1.02 each year. Over 15 years, this is 1.02^15 { ... | |
| Ratios | 2/24/2009 |
| Q: A group of 10 employees in an office decide to contribute $1.00 to a lottery. Nine of the employees ... A: That sounds like the most logical route, but with 9 employees, there's bound to be one in there who ... | |
| Bayes' Theorem | 2/19/2009 |
| Q: OK I got into an argument today because my co-worker told me he won all this money last time he ... A: Case 1: There is no probability of something happening that's already happened. The chance of the ... | |
| Karnaugh Maps | 2/19/2009 |
| Q: I can't seem to figure out how to simplify this boolean expression using a four-variable map. I ... A: I have never heard of Karnaugh Maps. I looked it up and found the Karnaugh Maps are using booean ... | |
| Matrices and Complexe numbers. | 2/18/2009 |
| Q: 1a). Let P be an invertible nxn matrix. Prove that (P^-1)^T= (P^T)^-1 (You may use the fact that ... A: According to en.wikipedia.org/wiki/Transpose , we know that (A^T)^-1 = (A^-1)^T, so that's in the ... | |
| fourier series | 2/17/2009 |
| Q: need some help with the following question. Determine the fourier series of the signal f(t) = 1+t/pi ... A: A Fourier series is defined by 0.5a0 + sum(from n=1 to ∞)an*cos(nx) + sum(n=1 to ... | |
| eleven fold | 2/17/2009 |
| Q: I would like to know the possibilities from a eleven fold from 13. i am told there are 78 ... A: It looks like you are choosing 11 objects from 13 possibilities. That sounds almost like a question ... | |
| Differentiation of 1st order | 2/17/2009 |
| Q: how to begin solving this? Please guide me and give me some hints. two variables x & t are connected ... A: Divide both sides by x/(10-x) and multiply both sides by dt. Yes, dx/dt really is a fraction. You ... | |
| Differential equation first order | 2/17/2009 |
| Q: i know how to do (i). But i dont know how to continue the rest. Please guide me. Here are the full ... A: Let n be the fish population. That's really n(t) where t is time. What this question says is that ... | |
| First order differential | 2/17/2009 |
| Q: I dont know how to begin. Please guide me. The amount A grams of a given carbon isotope in a dead ... A: i) The derivative of an exponential e^(kx) is ke^(kx), which is just k times the original function. ... | |
| finite math | 2/17/2009 |
| Q: find the slope ------------------------------------------------------------ (-2,5) and (4,7) ... A: find the slope - the slope of this is (y2-y1)/(x2-x1) where (x1,y1) and (x2,y2) are the two points ... | |
| sum | 2/16/2009 |
| Q: Evaluate: Σ[log k] over all k where k is a factor of 1 000 000 000 000 except 1 and 1 000 ... A: There are 12 0's, so the factors are 2^i*5^j where i,j go independently from 0 to 12. You'll have ... | |
| Statistics | 2/16/2009 |
| Q: "Here is the problem I am working on: An appliance dealer sells three different models of upright ... A: a) To get the expected value, take each x (13.5, 15.9, and 19.1) times each p (0.2, 0.5, and 0.3) ... | |
| Angle of elevation | 2/16/2009 |
| Q: Two observers are 500 feet apart. Each measures the angle of elevation of a hot air balloon that ... A: The angles are 53° and 42°. Since the larger angle is 53, the angle with the ballon and the other ... | |
| Discrete Random Variables and Probability Distributions | 2/16/2009 |
| Q: I'm having trouble grasping the "Probability Mass Funtion"(pmf) and "Cumulative Distribution ... A: Two dice: To get a 1, both dice must be a 1, so it's (1/6)(1/6) = 1 /36. To get a 2 or less, it ... | |
| real analysis - sequences | 2/15/2009 |
| Q: Ok so I have made some claims about sequences, and am having a bit of trouble writing out the proofs ... A: #1 If a sequence converge on some point monotonically (whether from above or below), the sequence ... | |
| QA | 2/13/2009 |
| Q: Please answer the below mentioned question, as i m unable to find the answer of it anywhere. A ... A: I would calculate the standard deviation on the entire set of numbers. I would then average the ... | |
| QA | 2/13/2009 |
| Q: Please answer the following question, Nonstandard dice can produce interesting distributions of ... A: One die will have a 1/6 chance of rolling a 1, 2, 3, 4, 5 or 6. The other die will have a 1/2 chance ... | |
| Problem Solving | 2/13/2009 |
| Q: A man set out at noon to walk from Point A to point B, and his friend started out at 2 pm from point ... A: Man 1: Left point A at noon, Man 2: Left point B at 2pm. Took identical paths, met at 4:05. I will ... | |
| Boolean Algebra | 2/12/2009 |
| Q: I need to find the complements of the following functions but I can't seem to get the right ... A: I will use C() as the complement, u as union and n as intersection, and S for the entire space. I ... | |
| Real Analysis | 2/11/2009 |
| Q: . You've been veryy helpful.. I have a few more questions for you about my proof class. 1. Suppose ... A: I understand, 'Suppose that the sequence (an) has limit L and that the sequence (bn) has limit K' ... | |
| maths probability | 2/10/2009 |
| Q: A person draws 6 cards from a deck of 52 cards. What is the probability that he has a royal ... A: Now that I am almost at the bottom, you are right in this case - it should be a 4 since there are ... | |
| Percentages | 2/10/2009 |
| Q: I saw this solution in an old mathematics book. I cannot understand how the solution to the answer ... A: To find 4% of a number means multiply the number by 0.04. In other words, 4% of 400 is 0.04*400 = ... | |
| problem with Horner method | 2/10/2009 |
| Q: i have a problem with horner method,and want you to just give me a short description about it,and ... A: I hope a better way would be to put the variable that is being divided above the problem, like 3 | ... | |
| maths probability | 2/9/2009 |
| Q: A house has 12 rooms (10 bedroom and 2 living rooms). We want to paint 4 yellow, 5 red and 3 ... A: There are 12 rooms with 4, 5, and 3 the same color, which would be 12!/(4!5!3!) ways to do it. ... | |
| On vectors | 2/9/2009 |
| Q: i dont know how to get started with this as i dont understand this topic. Please guide me. the line ... A: Line L has the equation r = (7i+0j+3k)+ t(5i+3j+2k) = (7,0,3) + (5,3,2)t. Plane ¥ has equation ... | |
| Related to vectors | 2/9/2009 |
| Q: the line l_1 passes through the point A,whose position vector is i-j-5k, & is parallel to the vector ... A: A is (1,-1,-5), L1 passes through A, direction (1,-1,-4). B is (2,-9,-14), L2 passes through B, ... | |
| 3d vectors | 2/9/2009 |
| Q: I dont understand this topic. Please help me, i need the whole solutions. The points A,B,C and D ... A: A is at (1,-1,2) B is at (3,7,-1) C is at (4,15,10) D is at (2,18,2) L passes through A and B ¥ is ... | |
| Vectors in 3d | 2/9/2009 |
| Q: can you explain the whole solutions steps by steps? the point A has position vector i+2j+3k,the line ... A: A is at (1,2,3) Line is (1,4,-1)+(1,-1,1)t Plane: -x+2y+2z=2 Points in plane A = (-2,0,0), B = ... | |
| Quiz qustion | 2/9/2009 |
| Q: Am in need of a good brain as mine is quite defficient regarding anything mathmatic. This is theA ... A: I don't know anything about her zodiac, but can say she is 29 and it is the 29th just before her ... | |
| trig | 2/8/2009 |
| Q: i have two questions. what is the quadrant terminal of 7 pi over 8? If A is in quadrant IV, and ... A: Now π/2 is the same as 4π/8, and this is less. The number π is the same as 8π/8, ... | |
| Vector in 3 dimension | 2/8/2009 |
| Q: If you know, can please you give me as many sites as possible which i can learn on the topic vector ... A: Here is a site that has several chapters that tell you all about 3d vectors. They include dot ... | |
| Algorithms | 2/7/2009 |
| Q: A clear picture of the question is attached, please help,Thank you. A: THat was a quick algorithm. It only took three steps. The significance is that 6 is one of the ... | |
| Cubic Formula | 2/6/2009 |
| Q: i need some help please... Use the cubic formula to solve this: x^3 + 4x^2 - 5x -3 Thanks A: The cubic formula to solve ax3+bx2+cx+d=0 is x = {q + [q² + (r-p²)^3]^0.5}^(1/3) + {q - [q² + ... | |
| Real Analysis | 2/5/2009 |
| Q: So here are 2 questions that are stumping me.. if you could help that'd be amazing! Before we ... A: 1. If supA < supB, then there exists some number b that is in B that is greater than supA. Take ... | |
| drawing conclusions | 2/4/2009 |
| Q: Please see the attached image. This problem requires me to figure out an algorithm is not correct ... A: The simplest way that I can find to do it is this. Right down the matrix, and then circle each ... | |
| Geometric Series | 2/4/2009 |
| Q: The first term of a geometric series is 27, the last term is 8 and the sum of the series is 65. What ... A: I recognize 27 as 3*3*3 and 8 as 2*2*2, so I will try 3*3*2 and 3*2*2 as the two middle terms. ... | |
| Real Analysis | 2/4/2009 |
| Q: Erik had a conjecture that said: If X is a subset of the real numbers and a is in set X and a is an ... A: If a is an upper bound for X, then this means that a≥t for any t in X. If we choose b<a to ... | |
| math | 2/3/2009 |
| Q: How many different selections of 3 cards can be made from the 12 face cards? How many choices do ... A: The answer is 12 choose 3, or, 12!/((12-3)!3!). 12-3=9, so we have 12!/9! = 12*11*10*9!/9! = ... | |
| turn powers of sin into multiple angles (nθ) | 2/2/2009 |
| Q: using z - 1/z = j2sinθ find sinθ cube. Example : sinθ to the power of 4 equals : ... A: Well, if sin^4(Θ) = (cos(4Θ) - 4cos(2Θ) + 4)/8, then it can be said that ... | |
| summation of equation | 2/1/2009 |
| Q: abe the following is a summation of equation problem that I don’t understand at all: 6 ... A: It looks like you tried to multiply ever value of k by -3 or something. The summation means to put ... | |
| Functions | 1/30/2009 |
| Q: I'm having difficulty helping/answering my daughter with this math question. Any light you can shed ... A: a. Yes, don't worry - you still remember it well. b. The answer to b is what the equation that fits ... | |
| statement problem - mba | 1/30/2009 |
| Q: can u please help solve this problem showing in detail the calculation Kleen Karpet cleaned 65 rugs ... A: Labor productivity is defined to be the ratio between output versus input. There were 520 hours at ... | |
| Iterative formula | 1/30/2009 |
| Q: State the no. Of roots of the equation 3e^(.5x)=4x+6. Taking 4 as a first approximation to 1 root c ... A: Thje fuction is 3e^(.5x)=4x+6. Divide both sides by 3 and then take ln() on both sides. When ... | |
| Integration by substitution | 1/30/2009 |
| Q: Find the exact value of the integration of x(sec^2)x with limits 0 to pi/3. Using the substitution ... A: I'll restate the answer with normal characters. I() = integral ANSWER: Find the exact value of the ... | |
| Numerical method | 1/30/2009 |
| Q: I understand this topic a bit only & i'm lack of resources on this topic. I'm wondering if you can ... A: (a) Here are my results: xn 4 exp(x) -4+EXP(x) -- - ------ ----------- ... | |
| correlation between scales... loss of granularity and other distortions (?) | 1/30/2009 |
| Q: There is wine in thisWhen it comes to classifying wine, a 50 to 100 point scale is used major ... A: x<70 @ the 0-100 scale, irrelevant; x=70 @ the 0-100 scale, y=10 @ the 20 pts scale; x=98-100 @ the ... | |
| correlation between scales... loss of granularity and other distortions (?) | 1/29/2009 |
| Q: There is wine in thisWhen it comes to classifying wine, a 50 to 100 point scale is used major ... A: It looks like the result is correct for the data given. If I read this right, one scale goes from 0 ... | |
| maths----probability | 1/29/2009 |
| Q: There are 40 students in a class. What is probability that no 2 students does not have same ... A: The number of ways they could all have birthdays is 365^40. For the first person, there are 365 ... | |
| Integration by substitution | 1/29/2009 |
| Q: Find the exact value of the integration of x(sec^2)x with limits 0 to pi/3. Using the substitution ... A: Find the exact value of the integration of x(sec^2)x with limits 0 to pi/3. Having read that, I'll ... | |
| Numerical method | 1/29/2009 |
| Q: I understand this topic a bit only & i'm lack of resources on this topic. I'm wondering if you can ... A: A) Use x0 as -2. Evaluate the function (4 - e^x)^0.5 with x=x0. In other words, calculate e^x, ... | |
| Iterative formula | 1/29/2009 |
| Q: State the no. Of roots of the equation 3e^(.5x)=4x+6. Taking 4 as a first approximation to 1 root c ... A: State the no. Of roots of the equation 3e^(.5x)=4x+6. When you look at the functions, both of them ... | |
| Number | 1/29/2009 |
| Q: Why does 0!=1? A: Because of the true way factorials are defined. n! = ⌠∞ ⌡0 x^n e^(-x) dx. ... | |
| Identities | 1/29/2009 |
| Q: how do i express i = 100sin(θ) + 150sin(θ + Π/3) as Rsin(θ ± α) and ... A: I don't think there is a way to express this function with one sin() wave. We know that ... | |
| math | 1/28/2009 |
| Q: (d^2-5d-14)/(d^2-3d-10) A: I assume that you want this reduced, no? The top and bottom are both functions that can be ... | |
| Real Analysis (Proof) | 1/27/2009 |
| Q: 1. Prove that if x in set Q (rational numbers), y in set Q (rational numbers) and x < y, then there ... A: 1. If x is in the rational numbers, then x = a/b where a, b are both integers. If y is in the ... | |
| algebra word problem | 1/25/2009 |
| Q: a photo is 4 inches longer than it is wide. a 3-inch border is placed around the photo making the ... A: Let the photo have width w and height h. When you say 'longer than it is wide', I'll assume that's ... | |
| Algebra | 1/25/2009 |
| Q: I used the quadratic formula to try to solve this question, but I can't seem to get rid of k. I'm ... A: According to the quadratic formula, the solution to ax^2+bx+c is x=(-b +/- sqrt(b^2-4ac))/2a. Note ... | |
| depreciation math problems | 1/24/2009 |
| Q: Construction Equipment ran an article on calculating equipment depreciation. The delivered price of ... A: This is a devaluation of a tractor problem. The original price was $135,000. The price at the end ... | |
| Making a Frustum | 1/24/2009 |
| Q: I need to make a frustum. I have found how to make the frustum however, now I need to cut it out of ... A: I'm not sure where the angles were gottem from, but using r, R, and h, I have found a paper that ... | |
| Iterative process | 1/23/2009 |
| Q: An iterative process for finding this root is defined by X subscript =1,X subscript (m+1) = (X ... A: It looks like you have x[0] = 1. x[n+1] = (x[n]+1)^(1/3). Using this, x[1] = 2^(1/3), x[2] = ... | |
| Other iterative processes | 1/23/2009 |
| Q: Use the formula Xr+1=(1-X^2 subscript r)/5, where Xo=0,to find the positive root of the equation ... A: To find the next next in the series, x1, let x1 = (1-x0^2)/5, so x1 = 1/5 = 0.2. To find x2, all we ... | |
| Numerical methods | 1/23/2009 |
| Q: Show that the equation x=cos x-3 has a root between -4 & -3. Use an iterative method to calculate ... A: Well, a good way to solve this is with Newton's method and start with x0 = -4. The variable xn+1 is ... | |
| Pre-Cal Identities help | 1/23/2009 |
| Q: In the following exercise, perform the indicated operations, then simplify your answers by using ... A: The first identity you need is sec(x) is 1/cos(x). Now that everything is in cos(x), in two ... | |
| fractional percents | 1/21/2009 |
| Q: how do I find the percentage of a fractional number and another fractional number such as 1/8= (?)% ... A: A percentage is how many parts out of a hundred. For example, 1/2 is 50 parts out of 100, so it is ... | |
| factorization | 1/21/2009 |
| Q: how do I solve this question? Factorize: 51y^2 - 2580y - 39879 Please help if possible, thank ... A: Use the good old quadratic formula. You know, x1 = (-b + sqrt(b^2 - 4ac))/2a and x2 = (-b - ... | |
| pre-calc | 1/21/2009 |
| Q: I have a few questions dealing with my semester 1 exam for precalc that have been giving me trouble. ... A: For the first one, not that sin^2(x) + cos^2(x) = 1, so replace cos^2(x) with 1 - sin^(x). After ... | |
| combinations | 1/19/2009 |
| Q: The whole problem is that I am suppose to verify that (1+x)^n-x(1+x)^n+x^2(1+x)^n-...+-x^k(1+x)^n = ... A: I thought about this now and then and again and some more, and it finally came to me how to do it. ... | |
| As-level | 1/19/2009 |
| Q: 1) Simplify: a) 10/sqrt5 + sqrt 20 b) 1/sqrt2 (2sqrt2 – 1) + sqrt2 (1-sqrt8) 2) Find the ... A: 1) Simplify: a) 10/sqrt5 + sqrt 20 note that 10 = 2√5√5, so one of √5 can be ... | |
| Counting Change | 1/19/2009 |
| Q: Would it be logical to pay for something that costs $0.41 with the amount of $1.06, $1.00 plus a ... A: A wsie cashier would recognize that the nickle would be returned anyway. Seeing this, they would ... | |
| Counting Change | 1/17/2009 |
| Q: Would it be logical to pay for something that costs $0.41 with the amount of $1.06, $1.00 plus a ... A: Maybe if you added a dime to that payment, then your change would be 75 cents, or 3 quarters. Yes, ... | |
| Proration | 1/16/2009 |
| Q: Is there a method to prorate one value over several other values without having a difference ... A: In http://www.thefreedictionary.com/proration, the definition of proration is the proportional ... | |
| Demography | 1/16/2009 |
| Q: Demography: you, 2 parents, 4 grand parents, 8 great grand parents and so on. Thus 2^n. Go back ... A: Unlike math, people get to make choices. Some get divorced, some remarry someone else. I've heard ... | |
| Equation Substitution | 1/16/2009 |
| Q: For some reason or another I am having trouble with the following problem: "From the set of ... A: (1) p = 3q (2) pr = qs (3) (1/2)pr^2 + (1/2)qs^2 = (1/2)qt^2 Find ratio of t to r. Putting ... | |
| graphing rational functions | 1/16/2009 |
| Q: "What is the vertical asymptote(s) of f(x)= x^2-x-2/x^3-2x^2-5x+6?" A: I take it the x^3-2x^2-5x+6 is suppose to be on the bottom? If so, then factor it, and that will be ... | |
| nil potent matrices | 1/15/2009 |
| Q: Suppose we have a matrix A such that A^n=0. What are the properties of n? Has n been known to obey ... A: I not that n has do to be less than or equal to the number of rows (or number of columns) of a ... | |
| prob & stats | 1/15/2009 |
| Q: x 20 25 30 35 45 55 65 y 40 30 20 10 10 8 5 let x represent the age in yrs of a licensed driver, and ... A: b) To find the equation for the line, find N, Σx, Σx², Σy, and Σxy. Solve the ... | |
| Algebra | 1/14/2009 |
| Q: Could you please help Solve the following system of equation X+2y=2(1) X=7-2y(2) Not for sure ... A: This many questions is sometimes ignored for there being too many questions, but these can be done ... | |
| trig. | 1/13/2009 |
| Q: I wondered if you could simplify or give me ideas about how to start simplifying the following: A = ... A: I will assume that a and b are the other two angles in a right triangle. They will be referred to ... | |
| trig identities | 1/13/2009 |
| Q: [(2tanx)/(1-tan^2x)]+[(1)/(2cos^2x-1)]=[(cosx+sinx)/(cosx-sinx)] A: All you've got to do is remember that 1 is not really 1, but that 1 = sin²x + cos²x. You'll see ... | |
| recursion | 1/13/2009 |
| Q: what is the basic form of a recursive function , and why? A: A good example of a recursive function could be the way to program n! (n factorial). A basic ... | |
| Rate problem | 1/13/2009 |
| Q: A salesman drives from A to B, a distance of 120mi, at a steady speed. He then increases his speed ... A: We don't know what speed he started at, so let's call it X. If X were 40 mph (but it's probably ... | |
| Pre calculus help- word problem | 1/13/2009 |
| Q: he speed of the wind increased exponentially. 10 minutes after sunrise, the windspeed was twice what ... A: First, the problem states that the speed is increasing exponentially. Second, it states that it ... | |
| algebra | 1/13/2009 |
| Q: Y=2+3X3X-4 4X=5,6,7 Y=2+3X-4 4X=5,6,7 A: Y=2+3X3X-4 4X=5,6,7 Y=2+3X-4 4X=5,6,7? I'm not sure what needs to be done. For the first one, ... | |
| trig function? | 1/9/2009 |
| Q: I'm stuck on the followingIf 2x + y = pi/4 show that tan y = (1-2tanx- tan^2x)/(1+2tanx - tan^2x) ... A: OK. That wasn't hard - just took awhile, once I thought about it. The key to the problem is to know ... | |
| sum = product | 1/9/2009 |
| Q: We know that the geometric series gives us 1/(1-x) = Sum(n to inf)x^n for |x|< 1. How can I show the ... A: The way the problem is written, the answer is ∞, since each term is greater than one. ... | |
| inverse of laplace transform | 1/9/2009 |
| Q: I want to find the inverse of the following Laplace transform I attached the problem A: Gamma is g - see the function, you'll understand. For the curvy w, I'll use w itself (though if I ... | |
| How to find vertical and horizontal asymptotes for logarithms | 1/8/2009 |
| Q: Can you explain how to find vertical and horizontal asymptotes for the logs? Thanks Here are some ... A: With the function h(x)=2^x, this is defined for all x, so there is no horizontal assymptote. As x ... | |
| pre-cal | 1/8/2009 |
| Q: Find the angle between the vectors u=7i+2j and v=-4j. Find all solutions of the equation x^-625i=0 A: If Θ is the angle between the two vectors, then cos(Θ) is the dot product between the ... | |
| Geometry | 1/7/2009 |
| Q: what is the area of a triangle whose vertices are (-4, -3), (8, 7), and (8, -3)? A: The left side of the triangle (a single point) is at x=-4 and the right side (a vertical line) is at ... | |
| Trig | 1/6/2009 |
| Q: Find the exact value of each expression, and you aren't suppose to use a calculator. cos pi/3 + sin ... A: Both of these functions appear to have radians. To convert radians to degrees, multiply the angle by ... | |
| function tables prealgebra | 1/6/2009 |
| Q: Can't figure out the rule for the following table: x=6, 10, 12, 15, and blank y=54, 50, 48, blank, ... A: Look at the two values in columns next to each other, b=blank. 6 54 10 50 12 48 15 b b 0 Between ... | |
| Weight | 12/31/2008 |
| Q: A whole brick weighs 9 lbs. and half a brick. Calculate the weight of a brick and a half. Thanks ... A: There are two ways to read thisA) Is this suppose to read: 'A whole brick weighs 9 lbs. Add half a ... | |
| Calculus III | 12/31/2008 |
| Q: I have two questions, but i think they have some difference between them?? 1. Find the maximum and ... A: f'(x,y) is really 1 + dy/dx, since this is a product of x and y. To do this correctly, y must be ... | |
| absoulte value | 12/31/2008 |
| Q: a|=a and |a|=-a Proof if a=0 then |a|=a If a<0 then |a|=-a>a a?R then |a|=-a i can not ... A: a|=a and |a|=-a: I'm not sure what this is saying, but I know that it should say if |a| = a, then ... | |
| equation of linear | 12/30/2008 |
| Q: At first, sorry about my compositionally mistakes, i'm from Hungary. My question is, that i have two ... A: Both of the equations could be put in the for y = mx + b. The variable m is for the slope. If m is ... | |
| dividing circles | 12/29/2008 |
| Q: My 8-year old son wants to know if 360 is the maximum number of pieces a circle can be divided into. ... A: As usual, our children tend to be right. Divide a circle into 360 pieces, 1° each. Cut each in ... | |
| absoulte value | 12/29/2008 |
| Q: |a|≥a and |a|≥a Proof if a≥0 then |a|=a If a<0 then |a|=-a>a aєR ... A: |a|≥a and |a|≥a Proof if a≥0 then |a|=a If a<0 then |a|=-a>a aєR ... | |
| Calculus III | 12/27/2008 |
| Q: I have two questions, but i think they have some difference between them?? 1. Find the maximum and ... A: For 1, I get the following: The x,y values are on an ellipse 9x² + y² = 6. The extreme points ... | |
| Calculus III | 12/26/2008 |
| Q: I have two questions, but i think they have some difference between them?? 1. Find the maximum and ... A: 1. There may be a shorter way to do it, but I think of xy as a product of two functions. Note that ... | |
| problem with Horner method | 12/26/2008 |
| Q: i have a problem with horner method,and want you to just give me a short description about it,and ... A: Hormer's method is for dividing one polynomial by another. 3 | 2 -6 2 -1 | ... | |
| Solving linear inequalities | 12/25/2008 |
| Q: I'm working on a math course in college. I can't seem to understand how one type of linear ... A: When presented with this type of problem, the first thing to do is put the variables on one side and ... | |
| angle inside a hole | 12/23/2008 |
| Q: I always can measure the diameter at the top and bottom of the hole, and the depth of the hole. I ... A: I answered this one, but didn't compute anything. The bottom radius is R=0.1174/2. The top radius ... | |
| Angle inside a hole | 12/23/2008 |
| Q: I need to know how to figure out the angle from a smaller diameter circle at the bottom of a hole to ... A: Half of the diameter is the radius. Take the difference between the two radii and that would be the ... | |
| Substitution | 12/21/2008 |
| Q: Q: Use the substitution method to solve the following simultaneous equation : ... A: SOlve the first equation for x and substitue into the second equation. 2x + 5y = 12, so 2x = 12 - ... | |
| Calculus III | 12/19/2008 |
| Q: Notice that the curve given by the parametric equations x = 9−t2 y = t3−4t is symetric ... A: Solve the first equation for t in terms of x. Substitute this into the second equation for t and ... | |
| Mortgages | 12/19/2008 |
| Q: Hey, my question is extremely long, and I hope you don't mind helping me out with it, because I'm ... A: Income: 55K; take home: 49K Inherited: 25K, use for lawyer, closing, etc. 1. Take 49K*0.32 to get ... | |
| Exponential Growth Function Rules | 12/19/2008 |
| Q: This graph has the points, (1,12) and (0,8) the line is not very steep, and more toward the shallow ... A: Since the problem is in exponential growth, I would assume the function was suppose to be ... | |
| Calculus III | 12/18/2008 |
| Q: Notice that the curve given by the parametric equations x = 9−t2 y = t3−4t is symetric ... A: You might have already known this: dy/dx is really a fraction. Take an example: If y=x^3, then ... | |
| Correlation, Covariance | 12/18/2008 |
| Q: My major is Coastal Engg. I want to use TimeSeries calculations to translate some of my observations ... A: The correlation between u and v is how much these two variables are dependent on each other. If the ... | |
| Calculus III | 12/17/2008 |
| Q: Let L be the circle in the x-y plane with center the origin and radius 38. Let S be a moveable ... A: Since the factors of 38 are 2 and 19, it can be seen that only the 2 goes into the 24. Lets take a ... | |
| Relation in math | 12/17/2008 |
| Q: please tell write me briefly about Relation.please help me friend A: A relation in mathematics is a set of ordered pairs. For example, { (1,2),(3,5), (4,3), (100,45) } ... | |
| Distance | 12/16/2008 |
| Q: A trip was made from Pixley to Bugtussle. Day one- one quarter of the distance was traveled. Day ... A: I will assume that [was travelled] applies: Day one- one quarter of the distance was traveled. Day ... | |
| Help on Simplifying! | 12/16/2008 |
| Q: I am simplifying the equation: 3x^2-3x+x-1 and I am confused... Ultimately, the answer I am ... A: 3x²-3x+x-1 is the same as 3x²-2x-1 since -3x+x is the same as -2x. Try any x and this can be seen ... | |
| isomorphism | 12/15/2008 |
| Q: Define the isomorphism between the two groups * a b c a a b c b b c a c c a b * d e f d f d e ... A: Let a,b,c be 0,1,2 and the two variables be X and Y. The operation for this would be (X+Y) mod 3. ... | |
| straight line graph | 12/15/2008 |
| Q: in the following y is the dependent variable & x is the independent. a&b are constants what type ... A: 1. A regular xy graph with x as the abscissa and y as the ordinate. On the rest of them, I have ... | |
| Analytic Trig | 12/12/2008 |
| Q: Confirm the Identity: sin^6(x)+cos^6(x)=(cos^2(x)-sin^2(x))(1-cos^2(x)sin^2(x)) A: Multiply out the right side. (cos^2(x)-sin^2(x))(1-cos^2(x)sin^2(x)) This gives cos²(x) - sin²(x) ... | |
| one to one, proof | 12/11/2008 |
| Q: Let F: X--> Y. Prove that f is a one-to-one function if and only if F(A)INTERSECTIONF(B) = F(A ... A: There is a way to right an upside down U on the screen. It is intersection is alt-239. That is, ... | |
| Sampling Distribution of sample mean | 12/11/2008 |
| Q: Let a very small population consist of five numbers:10,20,30,40,50,each having probability of being ... A: Five numbers: 10,20,30,40,50 Chance of each: 0.2 (equally likely) Take 2, with replacement. The ... | |
| hypothesis- stat | 12/11/2008 |
| Q: A pharmaceutical manufacturer is concerened that the impurity concentration in pills does not exceed ... A: Maximum sought: 0.03 Standard deviation: 0.004 Average generated: 0.0307 (most like will result in ... | |
| Mathematical Foundations- Proofs and Logic | 12/10/2008 |
| Q: Sorry I am asking you another question, its just your the only one who could do this math.... A ... A: The frist 3 terms are given 1, 4, and 9. Each term after that is defined as ... | |
| Mathematical Foundations-Proofs and Logic | 12/10/2008 |
| Q: A relation R is defined on Z ('All Integers'=Z)by aRb if 5a=2b (mod 3). Prove that R is an ... A: An equivalence relation means each element in one set is mapped to a specific element in the other ... | |
| math | 12/10/2008 |
| Q: how many word can be arranged from "business" with only 2s are adjacent? ANSWER: There are 3 ... A: There are 8 letters and we have taken out 2 of them (s and s). That leaves six letters. The number ... | |
| Trig | 12/10/2008 |
| Q: I wasn't quite sure what this meant, but I wanted to know if you could help me find the four roots ... A: I'm not sure what you mean either, but note that I believe the four roots to be 1, -1, i, and -i ... | |
| Trig | 12/10/2008 |
| Q: I was wondering if you could help me figure out the exact value of the six trigonometric functions ... A: Note that in degrees, any measure x° is equivalant to (360+x)°. That would mean that 740° is the ... | |
| Trigonometry Identities | 12/9/2008 |
| Q: verify that sin^6x + cos^6x= 1-3sin^2x * cos^2x A: Note that the sum of a^6 + b^6 is a sum of cubes when the factors are a² and b². Using this, it ... | |
| Stats | 12/9/2008 |
| Q: I understand that a sample is a subset of a population of interest and a census is the entire ... A: When a sample is taken from a population, it only matters how big the sample was to determine the ... | |
| Analysis Hw | 12/9/2008 |
| Q: I am trying to figure out this question on my Analysis homework: Suppose the f and g are Riemann ... A: I will assume a and b are chosen. a) This is not true, for you could have f(x)=7 on [0,5] and ... | |
| compound interest | 12/8/2008 |
| Q: steve gave me a formula for the following starting balance $1000.00 and is compounded at the rate ... A: I read the problem as 10% every 30 days. It may be meant that it is really 10% per anum and ... | |
| Calculus | 12/8/2008 |
| Q: Consider the function f defined by f(x)=e^x(cosx) with domain [0,2PI] a. Find the absolute maximum ... A: Just for curiosity, PI is alos typed alt-227, which gives π. But PI is okay as well. ... | |
| math | 12/8/2008 |
| Q: how many word can be arranged from "business" with only 2s are adjacent? ANSWER: There are 3 ... A: There are 8 letters, so the ways of arranging them is 8!. This must be divided by 3! since there are ... | |
| trig | 12/8/2008 |
| Q: complete the missing values for the trig functions when tan x= 3/4 and csc x= 5/3 A: When the tan(x) = 3/4, the far side is 3 and the near side is 4 (but they could also both be ... | |
| Pre-cal | 12/8/2008 |
| Q: How do you find arctan of square root of 3 over 3 A: I will assume that the problem is arctan(√3/3). The solution is the angle whose tangent is ... | |
| Expenential Equation | 12/7/2008 |
| Q: I am really stuck! I believe there is an answer to my problem, it is just beyond me. I have ... A: These are the factors I need to recognize; 1) 0 - 5 days stay, there is no discount applied. 2) 6 ... | |
| Mathmatical Riddle | 12/7/2008 |
| Q: I'm Rick and I'd like to resolve a math riddle that conventionally is very easy to solve, but in the ... A: 3x10=30 is correct, so that's OK, and now the person has 30. From the 30, he takes 5. That means he ... | |
| trigonometry | 12/6/2008 |
| Q: It is known that sin(a-b)= sin 60 , sin a cos b = sin 30, the result of sin(a+b) divided by ... A: We are given [S1]sin(A-B)=sin(60°) and that [S2] sin(A)cos(B)=sin(30). It is known that [1] ... | |
| compound interest | 12/5/2008 |
| Q: steve gave me a formula for the following starting balance $1000.00 and is compounded at the rate ... A: Here is what I've been told: The original amount was $1,000.00. The interest rate is 10%. There are ... | |
| math and demography | 12/5/2008 |
| Q: This is kind of a different math question. I guess you can consider it to be a combination of ... A: I'll assume half of the population is women (which is failry close to what it is). Their birth rate ... | |
| Elimenation ad Substitution | 12/5/2008 |
| Q: I need to find out the answer to this question, using Elimenation or Substitution. Ian invested ... A: Divide the money into two pieces, A and 8000-A. 0.09(8000-A) + 0.10A = 740. Multiplying out give 720 ... | |
| Word Problem | 12/5/2008 |
| Q: Mary has $3.00 in nickels, dimes, and quarters. If she has twice as many dimes as quarters and five ... A: N=nickels, D=dimes, Q=quarters She has $3, so we know that (A) 300 = 5n + 10D + 4Q. She has twice ... | |
| Math word Problem | 12/3/2008 |
| Q: I have been stuck on a question for awhile and I was wondering if you would be able to help? I ... A: We must have equal distance between the center (x,y) and each of the points. Since distance if the ... | |
| pre- calculus trigonometric functions | 12/3/2008 |
| Q: To find the height of s pole, a surveyor moves 5o feet away from the base of the pole and then, from ... A: Distance from pole: 5 feet. Eye level height: 6.5 feet (boy, sure is tall - almost 7'). Angle to top ... | |
| precal | 12/2/2008 |
| Q: convert the polar equation to rectangular form 1. r^2= sin2theta 2. r= 3cos2theta A: 1. If r² = sin(2Θ), then we can say that r² = 2sin(Θ)cos(Θ) by one of the trig ... | |
| trig identities | 12/2/2008 |
| Q: Hey, My name is Ben and my class has a test coming up on trig identities. I wanted to do some extra ... A: 1) It is known that sin(9x) = sin(5x)cos(4x) + sin(4x)cos(5x). What we are given is 2sin(5x)cos(4x) ... | |
| Please check my answers only 3 | 12/1/2008 |
| Q: What is the equation of the straight line passing through (-1, -3) and (2, 5)? Where does this ... A: Is this sayting x = 1/8 (x-intercept) and y = -1/3 (y-intercept)? Yes, that is correct. The x ... | |
| Math question dealing with many fractions | 12/1/2008 |
| Q: Bottle A contains a solution of -6 teaspoons of R oil -3 teaspoons of B oil -3 teaspoons of L oil ... A: Note that bottle A has 14 ounces, of which 12 are taken and 2 put in B, so bottle A is used every ... | |
| Population growth or Decay | 11/30/2008 |
| Q: Certain animal, current population 350, is growing 3% each year if left to itself, but hunters kill ... A: Let x be the number of years. 1. The equation for each year is integer(350(1.03)) - 15, since these ... | |
| math | 11/27/2008 |
| Q: how many word can be arranged from "business" with only 2s are adjacent? A: There are 3 letters s. There are 5 other letters, and the way to arrange them is A=5!. Three ... | |
| maths | 11/27/2008 |
| Q: 1.find the determinant of the following 5x5 matrix 4 1 8 2 5 1 0 0 3 1 4 2 3 1 3 6 4 4 1 0 7 3 1 2 ... A: Sorry it took so long - I just got back from thanksgiving a few hundred miles away. 1) To find the ... | |
| Pre-calculus | 11/25/2008 |
| Q: I have to solve: 12sin^2(2x-1)+sin(2x-1)-6=0 on (0,2pi) and show step by step A: Let u = sin(2x-1). Our equation becomes 12u² + u - 6 = 0. This can be seen to be (4u+3)(3u-2), so ... | |
| Weighted Average | 11/24/2008 |
| Q: Can you solve the following by using a weighted average calculation? An investor has $30,000 to ... A: The number is 2/3 from 2% and 1/3 from 5%, so you take 1/3 of 2% and 2/3 or 5% giving 2(1 - 2/3)% + ... | |
| Weighted Average | 11/24/2008 |
| Q: Can you solve the following by using a weighted average calculation? An investor has $30,000 to ... A: Let A be the amount of one of the investments. 30,000-A is what we have left for the other ... | |
| pre - calc. vectors | 11/23/2008 |
| Q: well i was wondering if you could help me solve this question, it says: Let U = [2,3] and V = [-3,1] ... A: The vector U is [2,3] and the vecotr V is [-3,1]. To add vectors, add each of the componets of the ... | |
| triconometry | 11/21/2008 |
| Q: what is the value of sin 7 1/2? A: Trigonometry answer: Is that sin(7½) { which is sin(7.5) }? If so, I will assume the 7.5 is in ... | |
| Discrete Mathematics | 11/19/2008 |
| Q: Counting, Probability Distributions and Further Topics in Probability From a pool of 8 new hires, 4 ... A: The number of ways of doing this is 8 choose 4, \ which is 8!/(4!(8-4)!). The symbol ! is for ... | |
| standardizing a series | 11/19/2008 |
| Q: Good Morning, I have three sets of scores, each with different means and standard deviations. Each ... A: Is this correct? Yes. I will have one scale? Yes. At least that is on the means, anyway. The ... | |
| pre-cal/trig. | 11/19/2008 |
| Q: Some confusion when i have to explain what the value of A tells in this data given ... A: A will tell you the magnitude of the wave. B will tell you how far offset from the x axis the middle ... | |
| Solving Systems of Equations | 11/18/2008 |
| Q: Solving Systems of Equations using Elimination (with 3 variables) Here is the problem: -5x-z=2 ... A: Make the first equation -5x + 0y -z = 2, so now we have a y in the first equation. Either that or ... | |
| Solving Systems of Equation in Three Variables | 11/17/2008 |
| Q: I am in solving systems of equation in three variables part of my chapter and I am having trouble ... A: 1: Divide second equation (2a=12) by 2, giving the value for a. Subtract 3a from equation 3 ... | |
| Math | 11/16/2008 |
| Q: Scott, How to you divide a 12 inch circle into 16 equal parts? Thank you, Chris A: Cut the cricle in half with a line through the center and it's in 2 equal parts. Draw a line the ... | |
| Matrix Word Problem. | 11/16/2008 |
| Q: I am 21 years old and in a 1st year university algebra course. I am generally fine doing matrix ... A: A college dormitory has 200 students. Those who watch an hour or more of TV on any given day ... | |
| Maths/Normal distribution | 11/16/2008 |
| Q: Melons sold on a market stall have weights that are normally distributed witha mean of 2.18kg and a ... A: The probability we are asked to find is that of a melon being between 2 and 2.5 kg. Assume this if ... | |
| Trig help | 11/14/2008 |
| Q: I do not understand how to solve this problem: if t varies inversely as y^2, directly as m, and ... A: t varies inversely to y² means that t = C/y². t varies directly as m means t = Cm. t varies ... | |
| SPSS grief | 11/14/2008 |
| Q: My daughter (a university student herself) turned me on to this website coz I am really stressed ... A: I would look at the three case individually and find the mean and variance for each case. Do a ... | |
| binomial expansion | 11/13/2008 |
| Q: Can you please explain to me binomial expansion.I really dont get any of it, i mean i get pascals ... A: C(a,b) means a choose b, or a!/(b!(a-b)!). I will now describe the rows in Pascal's triangle. The ... | |
| percentage/statistics? | 11/13/2008 |
| Q: Wilson I use a data base ,access, for my handicapping hobble. I use gusseamation for some results. I ... A: Excel In Excell, the results can be put in columns A and B. In column C, put =if($A#=1,A$#,""). ... | |
| Comparing the variance of variances | 11/13/2008 |
| Q: I am investigating variances between projected and actual costs in my workplace and plan to ... A: In real life, statistics are used everywhere but they aren't quite right. For example, according to ... | |
| Comparing the variance of variances | 11/13/2008 |
| Q: I am investigating variances between projected and actual costs in my workplace and plan to ... A: Compute the variance of both samples. Let n1 be the size of the first sample and let n2 be the size ... | |
| vector spaces | 11/12/2008 |
| Q: If V is a finite dimensional vector space over F and if W is a subspace of V, prove that: a) W is ... A: a) Since V is finite dimensional and W is a subspace of V, then W is also finite dimensional. Since ... | |
| Probability | 11/12/2008 |
| Q: A pair of dice, one red and one green, are tossed. A random variable is defined by subtracting the ... A: I have attached an image file. Here is the description. The left side is the rolls of the green die ... | |
| Comparing the variance of variances | 11/12/2008 |
| Q: I am investigating variances between projected and actual costs in my workplace and plan to ... A: I won't go into detail bu will mention that the variance is always known to be positive. The ... | |
| stumped... need an equation to solve these problems | 11/11/2008 |
| Q: have a steel cylinder 5 ft long with a diameter of 4 ft. -- 490 lbs per cubic ft. .... calculate ... A: The way to solve it is to take the length (5 ft) times the area of the circle. Note that the radius ... | |
| math proof, need a little help | 11/11/2008 |
| Q: Prove that 81 divides (10^n+1 -9n -10) for every nonnegative integer n. I have tried to do this ... A: (A) Term n+1 is 10^(n+2) - 9(n+1) - 10. Term n is (10^n+1) - 9n - 10). The difference between them ... | |
| Proofs | 11/11/2008 |
| Q: Let X and Y be elements of the set of intergers. Prove that if 3 does not divide X and 3 does not ... A: If 3 does not divide x or y, we have four choices: (A) x=3n+1, y=3m+1 (B) x=3n+1, y=3m+2 (C) x=3n+2, ... | |
| IMP 4 ( It's Trig I think....) | 11/10/2008 |
| Q: On a cold winter day a house is heated until it is warm enough for the thermostat to turn off the ... A: I think it would be done by using a cos() function that had a zero when the thermostat went off and ... | |
| IMP 4 ( It's Algebra I think....) | 11/10/2008 |
| Q: The approximate number of hours between sunrise and sunset in Oregon varies throughout the year as a ... A: a) The equation would be a sin wave. Compute when March 21st is (I believe its the 80th days of the ... | |
| IMP 4 ( It's Algebra I think....) | 11/10/2008 |
| Q: Mike and Sarah are playing a fun game in which they spin around on an office chair while holding a ... A: a) Assuming she is spinning sideways and releasing the ball of the side of the chair, we have a ... | |
| integration | 11/9/2008 |
| Q: Calculate a)integral (e^x) (sqrt(1-e^2x))dx b)integral (x^2)(e^-2x) thank you very much for your ... A: a) let u=e^x, then du=e^x dx The integral become the integral of √(1-u²)du. Let the ... | |
| Derivatives | 11/9/2008 |
| Q: Please find derivative of ax^2+b/cx+d Thank you. A: The derivative of x^n is nx^(n-1), so is the function is ax² + (b/c)x + d? If it is, the derviative ... | |
| quadratic equation | 11/8/2008 |
| Q: for what value of k,(4-k)x^2+(2k+4)x+(8k+1)=0,is a perfect square. sir,please tell with suitable ... A: To be a square, let's take x+a and square it. The result is x² + 2ax + a². Note that we have a ... | |
| Calculus | 11/8/2008 |
| Q: Let a and b be elements of the set of integers. Prove that if a+b and ab are of the same parity ... A: We have four choices. 1) a odd, b odd, 2) a even, b odd, 3) a odd, b even, and 4) a even, b even. ... | |
| Factoring quadratic equations | 11/7/2008 |
| Q: we are learning to factor quadratic equations in my online college algebra class and I'm so LOST! ... A: Note which terms are the same in each factor. I will look at each of the terms in order on each of ... | |
| Algebra 1 | 11/6/2008 |
| Q: Suppose that a market research company finds that at a price of p=$20, they would sell x=42 tiles ... A: This is constructing a line with y as p. The first point is (x1, y1) = (42,20). The second point ... | |
| Finite Math: Probability | 11/6/2008 |
| Q: Here is theTwo people play a game. A single die is rolled. If the outcome is a 3, then A pays B ... A: There are 6 ways a die can be tossed. 1/6 of the time, the player gets $3, so we'll call that $3/6 ... | |
| please elaborate | 11/5/2008 |
| Q: Please give me the answer in detail. A: The null hypothesis is the H0:σ<=2. The alternative hypothesis would be the H1:σ>2. ... | |
| ring homomorphisms | 11/4/2008 |
| Q: Let phi: F->R, F a field, R a ring and phi a homomorphism of rings. How do I show either phi(a) = 0 ... A: Let σ: F->R F a field R a ring σ a homomorphism of rings How do I show either σ(a) = ... | |
| probability | 11/3/2008 |
| Q: A telescope manufacturer wants its telescopes to have standard deviations in resolution to be ... A: The null hypothesis is the H0:σ<=2. The alternative hypothesis would be the H1:σ>2. ... | |
| Trig | 11/3/2008 |
| Q: Sin(2x-(pi/3))=1/2 A: Noe that 1/2 = 0.5. Take the inverse sin of both sides of the equation, so that 2x-π/3 = ... | |
| Algebra II | 11/1/2008 |
| Q: Can you answer this problem?? ax^2+bx+c=0 using the method of completeing the square of quadratic ... A: This is the original problem ax² + bx + c = 0. Move the loose number over to the other side, ... | |
| help!! | 11/1/2008 |
| Q: i've worked out these problems already, i would just like to know what you would get! :) 21. The ... A: The ratio of the present ages of two museums is 3 to 5. Twelve years ago, the sum of their ages was ... | |
| stastics | 11/1/2008 |
| Q: A central university has a student population of 60000.The university is interested in determining ... A: The Z table has the value between 2.05 and 2.06 somewhere, so let's call it half 2.055. σ is ... | |
| stastics | 10/31/2008 |
| Q: A central university has a student population of 60000.The university is interested in determining ... A: This looks like a binomial distribution. The average is np where is the number of students and p is ... | |
| stuck and need some help | 10/30/2008 |
| Q: Mr Wilson, I hope you can help me . I'm stuck on these problems and I'm running out of time on this ... A: First, note that B could be placed anywhere on the circle and that the angle would always be the ... | |
| permutation and combination | 10/30/2008 |
| Q: Can you show me cleary that the arrangement of n-different things taking r at a time ,such that ... A: I'll assume by (xPy), you mean what I formally write as P(x,y) which is x!/((x-y)!y!). If we have n ... | |
| pre-calc | 10/30/2008 |
| Q: i was wondering if you could solve this problem for me. thanxs a lot: tan(x)- (sec^2(x)/tan(x)) A: I find it best in my experience to convert everything to sin(x) and cos(x). Now tan(x)=sin(x)/cos(x) ... | |
| Trig Identities. Please help. | 10/29/2008 |
| Q: 1+ sin x = cos^2x/1-sin^x A: I assume the problem is 1+ sin(x) = cos²(x)/(1-sin(x)) since this can be proved by knowing that ... | |
| Math -- model fitting | 10/29/2008 |
| Q: The following data represents (hypothetical) energy consumption normalized to the year 1900. Plot ... A: YOu need to find a and b, and get the use Excel to put down the x's in one column and the Y's in the ... | |
| help in logarithms | 10/29/2008 |
| Q: I am mihir talreja studying in 11th standard . i am not able to solve problems with the help of ... A: 1. The logarithm is the power of a number. When ln() is used, the base e, where ... | |
| maths statistics | 10/29/2008 |
| Q: (a) The time, X minutes, taken by Fred Fast to install a satellite dish may be assumed to be a ... A: (i) P(X<µ+1σ) find a normal table (ii) Look up 0.100 on a normal table, call it x; time is ... | |
| Discrete Mathematics: Recursive function | 10/28/2008 |
| Q: .. I'm pretty bad with recursive function.. and was wondering if there's any way to improve on that. ... A: Given this, A(0,0) = 1, A(0,1) = 2, A(0,2) = 3, and A(0,3) = 4. Next we note that A(1,0) = ... | |
| Math -- model fitting | 10/28/2008 |
| Q: The following data represents (hypothetical) energy consumption normalized to the year 1900. Plot ... A: The problem really depends on whatQ=aebx means. Is that ae^(bx)? You need to find what some values ... | |
| Algebra | 10/28/2008 |
| Q: 15x^4 - 19x^2 + 6 = (x + 18)(x - 11)(x + 12) > 0 A: I will take it you are trying to factor the first expression. The quadratic gives ... | |
| Discrete Mathematics | 10/27/2008 |
| Q: Chapter 6- Systems of Linear Equations and Matrices Use the inverse of the coefficient matrix to ... A: 1 1 0 2 1 2 -1 1 -1 1 3 3 2 -2 1 1 2 1 0 1 The multipliers are 1, -2, -3, and -1. The ... | |
| Factorials | 10/27/2008 |
| Q: Hey - I'm prepping for the GREs and it's making me go back to high school problem solving that I ... A: I checked in a spreadsheet and put down 000 through 999. If any of the digits were 5, I tossed them ... | |
| Quadratic-like equations | 10/27/2008 |
| Q: Solve for x: 3x^4 - 22x^2 + 7 = 0 I get x = plus or minus the square root of seven and x = plus ... A: √3/3 is the same as 1/√3 . All that has to be done is to multiply by √3/√3 ... | |
| Factorials | 10/27/2008 |
| Q: Hey - I'm prepping for the GREs and it's making me go back to high school problem solving that I ... A: There are 10 choices for each digit under normal circumstances, so there are 10*10*10=1,000 choices ... | |
| checking over problems | 10/26/2008 |
| Q: Can you please check these for me? I am more confident of my answers this time. 1) Write the ... A: It looks like you’re guessing at the answers, for almost all of them are wrong. If you knew what ... | |
| Quadratic-like equations | 10/26/2008 |
| Q: Solve for x: 3x^4 - 22x^2 + 7 = 0 I get x = plus or minus the square root of seven and x = plus ... A: Just going at the problem, it can readily be seen that it factors into (3x²-1)(x²-7). The answer ... | |
| maths probability/statistics | 10/26/2008 |
| Q: A company analyses the servicing of machinery at one of its large factories. When a machine is ... A: As I understand the problem, we are given P(B)=0.1, P(BuC)=0.28. (a) (i) Since B and C are ... | |
| Algebra | 10/26/2008 |
| Q: I can't figure this out, can you help? Please! (6x-5)^2(3x+1)^2 Can you please show the work so I ... A: Sorry about that, but I think I misread you're problem. If you have (ax-b)², the answer is a²x² + ... | |
| ALGEBRA | 10/26/2008 |
| Q: I AM STUCK AND CAN'T FIGURE THIS OUT. I HOPE YOU MIGHT BE ABLE TO HELP ME FIGURE THIS OUT. Find ... A: If d=-6, e=-7, and f!=23 (f is not equal to 23), then there is no solution. You might also have ... | |
| Math | 10/24/2008 |
| Q: Determine whether the argument is valid or invalid. A tree has green leaves or the tree does not ... A: The problem states that has one of two things green leaves does not produce oxygen When it ... | |
| Discrete Mathematics | 10/24/2008 |
| Q: Solve the system by Gauss-Jordan Method. x - y = 2 x + y = 4 2x+3y = 9 3x-2y = 6 A: The Gauss-Jordan method of solving states that the first term in each row should be 0 or 1 with 0's ... | |
| Algebra | 10/24/2008 |
| Q: I can't figure this out, can you help? Please! (6x-5)^2(3x+1)^2 Can you please show the work so I ... A: When we are solving for when this function is zero, we get (6x-5)²(3x+1)²=0. The only two x values ... | |
| help | 10/23/2008 |
| Q: Tim. I chose (b) for the answer. If it is wrong can you please provide the correct answer with ... A: I'll assume there are equal angles in this trapezoid at the base and at the top (at least that's the ... | |
| quick calculation | 10/23/2008 |
| Q: Please let me know if u know the trick to make quick calculations. Like, for example 333 times 131.. ... A: For that specific example, yes. Divide 131 by 3 and you get 43 2/3. So the answer is 43,666 - 43 = ... | |
| Factoring Polynomials (PreCalc) | 10/23/2008 |
| Q: Factor this quartic equation: 4x^4-5x^2-6=0 A: Let z=x². The equation is then 4z²-5z-6=0. The quadratic equation will tell us the ... | |
| algebra | 10/22/2008 |
| Q: I have a few questions. 1. A pasture is twice as long as it is wide. Its area is 115,200 ft ... A: 1. Let w=width, then l=2w. 2*2w=115,200. Solve from there. 2. 0.6A+0.3(1-A)=.5; solve for A. It ... | |
| Discrete Mathematics | 10/22/2008 |
| Q: Chapter 6- Systems of Linear Equations and Matrices Hi, could you help me with this word problem. ... A: You have 4 variables, and only 3 equations. The variables are for brands A, B, C, and D. The ... | |
| mathematic | 10/22/2008 |
| Q: A central university has a student population of 60,000. the university is interested in determining ... A: The error value is approximately 1/√n. The ±0.02 with 95% confidence says the number of ... | |
| Trigonometry | 10/22/2008 |
| Q: cos(2tan-1x) The tan is inversed. A: Let's look at the inside first. To have tan^-1(x), we need to have far side x and near side 1, so ... | |
| maths probability and normal distribution | 10/21/2008 |
| Q: A manufacturer of dishwashers uses electric pumps from the 3 suppliers P,Q and R, in the ratios ... A: Name, supplies, fail P, 0.5, 0.08 Q, 0.3, 0.10 R, 0.2, 0.05 A) i) given Q, failure is 0.10 ii) ... | |
| Probability | 10/20/2008 |
| Q: Twenty married couples vacationing in Las Vegas participated in a contest. If 20 persons each win a ... A: That's it. You know, 2^20*(20*19*18...*3*2*1)/(40*39*38*...*23*22*21). You might be able to compute ... | |
| probability | 10/20/2008 |
| Q: In a large locality, 60 percentage of families have a car, 50 percentage have an air condition and ... A: Draw a square and quarter it with a horizontal line and a vertical line. The two squares on top ... | |
| maths statistics probability and normal distribution | 10/19/2008 |
| Q: At a station the probability that the first train in the morning is late is 0.4. Thereafter, the ... A: The first train is late is 0.4. A) For the first three to be late, we would have 0.4*0.6*0.6. B) ... | |
| Finite Math | 10/18/2008 |
| Q: Systems of Linear Equations and Matrices Write the augmented matrix of the system and use the ... A: The matrix would be 2 -1 2 3 -1 2 -1 0 3 -2 1 1 1 -1 1. Take the top row, 1st element, divide by ... | |
| Probability | 10/18/2008 |
| Q: Twenty married couples vacationing in Las Vegas participated in a contest. If 20 persons each win a ... A: Either the man or the woman of each couple could have won. This results in 2^20 possible ... | |
| Quantitative Analysis | 10/17/2008 |
| Q: A telescope manufacturer wants its telescopes to have standard deviations in resolution to be ... A: a) Null Hypothesis: The resolution is below 2 when looking at objects that are 500 light years away. ... | |
| Math | 10/17/2008 |
| Q: For sets A and B, determine whether A = B, A is a subset of B, or B is a subset of A ... A: If you look at the definition for A, it includes 14, 15, 16, and 17. If it was suppose to include 13 ... | |
| algebra | 10/17/2008 |
| Q: Given R(x)=x(2000-60x) and C(x)=40000+50 where x is thousand of computers and both functions have ... A: Isn't C(x) suppose to be 40,000 + 50x (the x is missing)? (note that I sort of like putting commas ... | |
| calculating e^At | 10/16/2008 |
| Q: As i heard there are about 12-13 ways to calculate e^At(A is a matrix)this term usually use in ... A: Here are a few http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.37.1874 ... | |
| algebra | 10/16/2008 |
| Q: The manager of a company manufacture surfboard has fixed costs (at o output)$500 per day and the ... A: As I understand it, the fixed cost is $500 / day, so this is a constant. The $6500 is the cost of ... | |
| Trig Proof | 10/15/2008 |
| Q: How do you verify that sin(a+b)=sinacosb+cosasinb?? Thanks. A: I aquired this out of http://www.phy6.org/stargaze/Strig5.htm Given the functions (sinα, ... | |
| algebra | 10/15/2008 |
| Q: I can't understand this question and would like some help. create a function that has a domain ... A: If the function can be any function, take y=ln(x + 7/9). The domain of ln(x) is x>0, so if we add ... | |
| Math | 10/14/2008 |
| Q: Scott, - If A B and B C, can you conclude that A C? Can you conclude ... A: What I see is this Scott, - If A B and B C, can you conclude that A C? ... | |
| math | 10/14/2008 |
| Q: please help!!! fA = bh (area of a rectangle) P = 2bh (of a rectangle) A rectangle has area 35 sq. ... A: x+y=12, so y=12-x, so x(12-x)=35, so x²-12+35=0 (that's how you got there), and now to find the ... | |
| Calculus 2 Proof | 10/14/2008 |
| Q: Can you give me a proof that the integral of (sqrt(1+x^2)) = ((x/2)(sqrt(1+x^2) + ... A: I sepnt several hours on this and when I finally came up with an answer, I took the derivative, but ... | |
| percents/interests | 10/13/2008 |
| Q: I need some help. Ok, say you have $445 put away in the bank. The interest is 3%. How much can I ... A: Take the 3%, divide by 12, and this is the monthly interest. Multiply 445*F/A, where F/A (future ... | |
| Calculus 2 Proof | 10/13/2008 |
| Q: Can you give me a proof that the integral of (sqrt(1+x^2)) = ((x/2)(sqrt(1+x^2) + ... A: I thought about this for a long time, and still can't seem to get it right. I'll give you what I ... | |
| Trigonometry equation | 10/12/2008 |
| Q: I have a problem with a trigonometry question. The question is: Solve for x, where x falls between 0 ... A: This factors into [sin(x)+3(cos(x)][sin(x)-cos(x)] = 0. This can be turned into sin(x)+3(cos(x) = 0 ... | |
| 3D Vector Questions | 10/12/2008 |
| Q: I'm having a little difficulty with doing three of these math questions and since it's the school ... A: I thought about sending a follow up on how to do 1 better, but you gave me 10 out of 10 ratings, so ... | |
| Arithmetic Series/ Geometric Progression | 10/12/2008 |
| Q: i am unsure how to answer the followingFind the sum of squares of the first n odd integers. I think ... A: Look at each of the terms. For n=1, the sum is 1. For n=3, the sum is 1+9=10. For n=5, the sum is ... | |
| strategies for problem solving | 10/11/2008 |
| Q: time, rate, and distance? Bob has an important presentation to deliver at the meeting and needs to ... A: The amount of time for the train is gotten by taking the 30 minute stop plus the 156 miles divided ... | |
| Re: Maximum and minimum points in quadratic graphs | 10/11/2008 |
| Q: I previously asked a question about how to know id the coordinates of the maximum/minimum points are ... A: The numbers are (1,-4). This means that x is 1 and y is -4. The signs of the numbers are just the ... | |
| Qunatitative analysis for managerial application | 10/10/2008 |
| Q: Q.1) In a locality 60% of families have a car, 50% have an air conditioner and 30% have both Find ... A: Q1) You are given P(A), P(B), and P(A n B). The P(A u B) = P(A) + P(B) - P(A n B). a. At least 1 is ... | |
| excel formula | 10/9/2008 |
| Q: what is the excel formula for calculating yearly growth stated by month. i.e. last year's sales ... A: If this is as simple as it might seem to be, all you have to do is take 15/12 [ or 5/4 ] and ... | |
| Maximum and minimum points in quadratic graphs | 10/9/2008 |
| Q: I have used the completing the square method for a quadratic equation and wish to draw a graph on ... A: a) For a coordinate (4,5), both x and y are positive. b) For a coordinate (2,-6), only x is positive ... | |
| Geometry | 10/9/2008 |
| Q: Consider a 20-lb pink flamingo that stands 3 ft. tall and has 2-ft legs. Model the height and leg ... A: Hey - that question was added to my list while I was answering others. Anyway, ... They items that ... | |
| Proving Identities | 10/9/2008 |
| Q: I need to see how to prove this identity.. [sin(3x)-cos(3x)]^2 = 1-sin(6x) A: First, not that all mathematical problems, when done properly, convert the left side into the right ... | |
| math | 10/9/2008 |
| Q: 4sin[2Pi/5(1-0)] A: I think that the 1-0 is on the bottom of the fraction, even though if it is, it should be (5(1-0)). ... | |
| precalc - trigonometry | 10/8/2008 |
| Q: i just had a question about my homework. it goes like this: Solve for theta, 0 degrees < theta < 360 ... A: a. If a triangle is drawn with sin(Θ) = 1/2, make the opposite side 1. The hypoteneuse would ... | |
| pre-calc | 10/8/2008 |
| Q: Give an example of a rational function with the following characteristics: vertical asymptote: x=3/2 ... A: To have a vertical asymptote of 3/2, the function needs to be divided by (2x-3). Since there are no ... | |
| math proof | 10/7/2008 |
| Q: How to prove Fx1 = FX1Cos Theta + FY1Sin Theta and Fy1 = -FX1Sin Theta + FY1Cos Theta? The question ... A: Given a triangle, take A as the opposite side and b as the adjacent side. The hypoteneuse will be ... | |
| Pythagorian Claim | 10/6/2008 |
| Q: I was curiouse if you would be able to help me with this claim. I really need some help, I don't ... A: You've hit upon a subject I myself am interested in. I'm not sure what the number n, 7, 2 have to do ... | |
| Probability | 10/6/2008 |
| Q: what are sufficient conditions for N events to be independent here N stands for any number of events A: They need to have a random appearance on a graph that puts them in order. I believe that the ... | |
| Math Foundations-Proofs | 10/6/2008 |
| Q: Prove that if x is any real number greater than 2, then there is a negative real number y such that ... A: Take x=3, so we need a y such that 3=2y/(y+1). This converts to 3y+3 = 2y, or y = -1. Take x=4, ... | |
| binomial theorem | 10/4/2008 |
| Q: Please see the question attached. Thank you for your help! A: a. If you take all of the number from 1 to n times 2, that is all of the even numbers from 2 to 2n. ... | |
| On partial fraction | 10/3/2008 |
| Q: Express the following in partial fraction: (x^6-x^5-4x^2+x)/(x^4+3x^2+2) i have tried it many ... A: Yes, the values you got for A, B, C, and D are right. Note that the final answer is x[x-1 + ... | |
| Partial fraction | 10/3/2008 |
| Q: Express the following in partial fraction: (x^2+23)/((x+1)^3(x-2)) i have tried it many times for ... A: To solve a matrix, we need a 1 in each column and the rest of the values 0. When we're done, there ... | |
| help | 10/3/2008 |
| Q: Find a quadratic equation with integral coefficients having the given roots Ö= root sign iÖ 5 ... A: By the way, the squareroot symbol, √, is gotten by holding down on the alt and typing the ... | |
| Partial fraction ! ? | 10/2/2008 |
| Q: Express the following in partial fraction: (3x^3+2x^2+2x-3)/((x^2+2)(x+1)^2) i have tried it for ... A: This one is straight forward for on the top, x is only cubed, but on the bottom, it is taken to the ... | |
| Q. Partial fraction | 10/2/2008 |
| Q: Help how 2 do tis question? Express the following in partial fraction: ... A: The fractions is (2x^4 - 2x^3 + x)/[(4x^2 - 4x + 1)(x-2)]. Multiplying the bottom out again gives ... | |
| On partial fraction | 10/2/2008 |
| Q: Express the following in partial fraction: (x^6-x^5-4x^2+x)/(x^4+3x^2+2) i have tried it many ... A: The bottom factors in to (x²+1)(x²+2). First we must divide the bottom into the top to get a ... | |
| About partial fraction | 10/2/2008 |
| Q: Express the following in partial fraction: (2x^2-5x-5)/((2x^2+5)(4x-5)) i have tried it again & ... A: Solve the equation (Ax+B)/(2x²+5) + C/(4x-5) = (2x^2-5x-5)/((2x^2+5)(4x-5)). This changes to ... | |
| Partial fraction | 10/2/2008 |
| Q: Express the following in partial fraction: (x^2+23)/((x+1)^3(x-2)) i have tried it many times for ... A: The equations are A/(x+1)^3 + B/(x+1)² + C/(x+1) + D/(x-2). This can be all put over (x+1)^3(x-2) by ... | |
| pre-cal mixture problems | 10/2/2008 |
| Q: How many galleons of a 12% salt solution should be added to 10 galleons of an 18% salt solution in ... A: You have 10 gallons of 18% salt, adding gallons of 12% salt. What you will add will be x gallons. ... | |
| quantitative analysis | 10/1/2008 |
| Q: 1. Solve the following system of equation by Cramer’s rule. X1+ X2 + X3 = 10 5X1 - 2X2 + ... A: 1. Solve the following system of equation by Cramer’s rule. X1+ X2 + X3 = 10 5X1 - 2X2 + X3 = 3 3X1 ... | |
| Algebra | 9/30/2008 |
| Q: 1. Solve using the Elimination Method. a. 2r - 7s = -57 7r + 2s = 39 What is the solution set ... A: 1. Solve using the Elimination Method. a. 2r - 7s = -57 7r + 2s = 39 Multiply the first equation ... | |
| autocorrelation and multicollinearity | 9/30/2008 |
| Q: Can you tell me anything about autocorrelation and multicollinearity? I have a few questions ... A: What I can say is there is a term called the autocorrelation coefficient. If it has the value 1, ... | |
| Algebra | 9/30/2008 |
| Q: 1. Solve using the Elimination Method. 2r - 7s = -57 7r + 2s = 39 What is the solution set ... A: 1. Solve using the Elimination Method. 2r - 7s = -57 7r + 2s = 39 What is the solution set ... | |
| Percent in Original Mixture | 9/30/2008 |
| Q: In a uniform seed mixture 1/25 is replaced with clover seed. The result is a mixture that is 10% ... A: We have replaced 1/25 with colver seed, which means that 24/25 have not changed. Let the unknown ... | |
| Algebra-Constraints/Linear programming | 9/30/2008 |
| Q: I'm having major problems with this specific subject.I don't understand it at all.Here's an example: ... A: The scale on the x values is between 0 and 5, so we can ignore (a) and (b) in doing the plot, since ... | |
| Demand Equation | 9/30/2008 |
| Q: Suppose that a market reseach company finds that at a price of p=$20, they would sell x=$42 tiles ... A: Note: I'll assume that the first question should have an x=42 tiles per month in it (no $) and ... | |
| regarding probability | 9/22/2008 |
| Q: 6 bicylists has to be chosen from 4 adult and 4 children cola: how many 3 adult and 4 children teams ... A: I'm not sure how col A and col B are suppose to relate, but here's is how to determine the number in ... | |
| The golden mean ratio | 9/22/2008 |
| Q: What is the Golden Mean Ratio? A: 1st Answer ---------- The Golden Ratio was in the title. Now I could say that The Golden Ration is ... | |
| combonations | 9/16/2008 |
| Q: say you have the following formula 46!/[6!*(46-6)!] aka 46 C 6. what would the answer be first off? ... A: The answer would be computed as 45*45*44*43*42*41/(6*5*4*3*2*1). 46! isn't computed on calculators ... | |
| pre-calc | 9/14/2008 |
| Q: Hey I'm in freshman in pre-calc and I've been working on this 100 problem worksheet and I'm down to ... A: 1. When numbers are multipled, add the exponets, then subtract off the expoents on the bottom. We ... | |
| SAT math | 9/14/2008 |
| Q: In the xy-coordinate plane, the graph of x=y^2-4 intersects line L at (0,p) and (5,t). What is the ... A: If L intersects the curve at two points. One is at (0,p), so the possible values of p are solutions ... | |
| Arthur's Arithmogons. | 9/11/2008 |
| Q: My question is in respect to arithmogons and pattern seeking. I have a book titled Mastering ... A: Call the endpoint x, y, and z. To solve the first one, we have to solve x+y=49, x+z=37, and ... | |
| Matrices | 9/10/2008 |
| Q: I have a couple more questions for you, both involving matrices. I have an original matrix that is ... A: Row echelon form says nothing about deleting columns. To be reduced to proper form, divide R2 by 3. ... | |
| combinations of numbers that sum to a given total | 9/9/2008 |
| Q: I'm developing some Killer Sudoku software and have come up with a requirement to find out how many ... A: The first response was apparently wrong since I allowed duplicates to occur. I had tried to insert ... | |
| combinations of numbers that sum to a given total | 9/9/2008 |
| Q: I'm developing some Killer Sudoku software and have come up with a requirement to find out how many ... A: Also, note that the reason at 4 there are three choices is because we also have to worry about which ... | |
| STATISTICS | 9/9/2008 |
| Q: HELP PLEASE :) YOU HAVE A DECK OF 52 CARDS. YOU ARE TO DRAW 4 CARDS. WHAT IS THE PROBABILITY THAT ... A: (4 C 1) = 4!/((4-1)!1!) = 4!/(3!1!) = 24/6 = 4. (48 C 3) = 48!/(45!3!) = 48*47*46/3*2*1 = 17,296. ... | |
| algebra | 9/8/2008 |
| Q: Six month ago ,an investment company had a $3,100,000 portfolio consisting of blue-chip and glamour ... A: Is that current value suppose to be $3,240,000? There is no way it can drop from 3,100,000 to ... | |
| algebra | 9/8/2008 |
| Q: Investment club An investment club bought a bond of an oil corporation for $5000.The bond yields 8% ... A: The way I understand this problem is cement drivers were on strike for 46 days and want to get this ... | |
| logarithm | 9/8/2008 |
| Q: solve this question 0.7^x+1 equals 0.3^x. solve for X. A: I do not see how to find it exactly. I would use the bisection method with -1 and 1 as my endpoints. ... | |
| STATISTICS | 9/8/2008 |
| Q: HELP PLEASE :) YOU HAVE A DECK OF 52 CARDS. YOU ARE TO DRAW 4 CARDS. WHAT IS THE PROBABILITY THAT ... A: There are 52 cards. 48 of them are not an Ace and 4 of them are. 4 cards are to be drawn, with ... | |
| Quantative Decision Making | 9/6/2008 |
| Q: This is a linear program problem. Are the following objective functions for and LP model equivalent? ... A: A linear programming problems main equation must have one or more variables that are each in linear ... | |
| linear equations w multiple variables | 9/5/2008 |
| Q: I need to "maximise a+b+c" subject to 7a-6b-5c is < or = 0 & -9a +8b + 7c < or = 0 where a,b,c are ... A: I thought that using operations research would provide an initial answer so that I could see what a ... | |
| Midpoint and Distane | 9/5/2008 |
| Q: Scott, How do you find the midpoint and the distance of a segment without coordinates on a ... A: The way to do it is with a ruler and compass. We will call the line in question line 1. Using a ... | |
| Algebra 2 | 9/4/2008 |
| Q: What are the formulas for geometric and arithmetic mean? A: Let's do the arithmetic mean first, since it is more commonly used. ... | |
| absolute value | 9/4/2008 |
| Q: How am I to solve a problem with two sets of absolute values. This one I don't understand at all; ... A: If these are absolute values, the problem is to be typed |x-3|+|x+3|=6. To solve, note where the ... | |
| Algebra | 9/4/2008 |
| Q: Okay well i wanted to know what is....4 over 5 multiplied by 3 multiplied by 20 subtract by 17? A: There are several different ways to read this problem. If I read this problem as it's written ... | |
| algebra | 9/3/2008 |
| Q: Investment club An investment club bought a bond of an oil corporation for $5000.The bond yields 8% ... A: Since 5% is 1.5% less than 6.5% and 6.75% is .25% higher than 6.5%, inspection tells us that 1.5% is ... | |
| gradient | 9/3/2008 |
| Q: I need some help Use the gradient -y intercept method to graph: a. y=2x - 3 b. 4y=3x +8 c. 2x +3y ... A: When an equation is in the form y=mx+b, it passes through b on the y axis and has slope m. a. We ... | |
| Math Problem | 9/3/2008 |
| Q: The question is using line 1: x+5y=10, Find an equation to the line that passes through (-3, 5) and ... A: Take the equation y-5=(1/5)(x+3) and multiply out the parenthesis giving y-5=x/5+3/5. Add 5 and ... | |
| limits | 9/3/2008 |
| Q: How do I find the limit as x approaches 0 of ((1/(x+4))-(1/4))/x ? I do not know the process to ... A: I would take the equation ((1/(x+4))-(1/4))/x and simplify it. Multiply the 1/(x+4) times 4/4. ... | |
| linear equations w multiple variables | 9/3/2008 |
| Q: I need to "maximise a+b+c" subject to 7a-6b-5c is < or = 0 & -9a +8b + 7c < or = 0 where a,b,c are ... A: This is a linear programming problem with the top row as a+b+c. It would be written as such with an ... | |
| algebra | 9/3/2008 |
| Q: Investment club An investment club bought a bond of an oil corporation for $5000.The bond yields 8% ... A: To get the total volume, its height*width*depth. The height is 2. The width and depth are both ... | |
| Interest Rate Formula | 9/2/2008 |
| Q: I would like to know what the formula is to find out what interest rate is on an automobile loan if ... A: Given P and A, we have (r/12)/(1-(1+r/12)^-m)=A/P. I assume the number of months, m, is known as ... | |
| algebra | 9/1/2008 |
| Q: Investment club An investment club bought a bond of an oil corporation for $5000.The bond yields 8% ... A: Compute the interest rate on $0.50 out of $20 by multiplying both by 5 giving $2.50 our of $100, so ... | |
| Algebra | 9/1/2008 |
| Q: Factor w^2-7-12 A: Is the function really suppose to be w²-7w-12? (If not, it can't be factored). The choices to look ... | |
| math question | 8/30/2008 |
| Q: Evaluate the difference quotient for the given function. Simplify your answer. F(x) = x + 3 /x + 1 ... A: Take F(x) from the first equation and put it into the second equation. This gives you x+3/x+1 - ... | |
| Triganometry - trisverse | 7/30/2008 |
| Q: Can you explain the steps that I need to take in order to figure a triverse. Example, I have 3 of ... A: Use graph paper, 1"=200'. 1) 600' N is the same as 3" straight up/ 2) 500; N 30° E is the same as ... | |
| math | 7/29/2008 |
| Q: sir! i'm struggling with precalculus, can you send some precalculus notes, and you pls explain how ... A: All functions have what is called a domain and a range. The domain where the function is defined. ... | |
| tables. please my numbers look right? | 7/28/2008 |
| Q: can you give your email addres To follow up, I am sending you hierarchical regression results ... A: A great way to send them would be to highlight them all, do an edit-cut (or whatever you use in the ... | |
| solving a system in three variables matrices | 7/27/2008 |
| Q: I just start in this course i need to know the steps to perform, my problem is how do i know what to ... A: 1. These equations can be rewritten like 2., but using the values from equation 1. Note that I ... | |
| Equation of the form y = a sin[b(t - h)] + k | 7/26/2008 |
| Q: Table Time (months) Temperature ( ̊F) 1 34 2 ... A: a. Find the value of b assuming that the period is 12 months. The period of the sin curve is ... | |
| The Six Trigonometric Functions | 7/25/2008 |
| Q: Find the values of the six trigonometric functions at the angle theta. The point P(-3, 4) is on the ... A: Since the origin is the other point, the hypoteneuse is just the sqrt(3²+4²). Θ is the angle ... | |
| Solving For X | 7/25/2008 |
| Q: How would you solve for x in this equation 2^x + 2^(-x) = 5 A: I'd use a spreadsheet and put 2 in A1, 2^A1+2^-A1-5 in B1, 2^A2*(ln(2)+2^-A2*ln(2) in C1. In A2, ... | |
| abstract algebra | 7/24/2008 |
| Q: Scott, thank you for the help with the other questions I asked. I have another abstract algebra ... A: The rules to be a ring are as follows: Here we show these rules to be true. If a=b, then a mod n = ... | |
| Finding Inverse | 7/22/2008 |
| Q: Find the inverse of the function y = x^2 + 5x A: This can be rewritten as y = x(x+5). The inverse x=y/(x+5) can be started with, but where do we go ... | |
| Period, Domain, Range of Function | 7/22/2008 |
| Q: 1. y = 3csc(3x + π) - 2 2. y = 2 sin(4x + π) + 3 Determine a. the period b. the domain c. ... A: period (how often it repeats) ----------------------------- The period for csc(x) and sin(x) are the ... | |
| Mathematics | 7/22/2008 |
| Q: Solve the following equations for x and y: x + y = 5 x^y + y^x = 17 ANSWER: Try 0 and 5. Try 1 ... A: One of those was the exact solution - there's only two number to try. 1 and4 or 2 and 3. 1+4=5, 1^4 ... | |
| Abstract Algebra | 7/21/2008 |
| Q: Scott, I have an Abstract Algebra question. Let Zn = {0,1,...,n-1}under addition and multiplication ... A: It is an integral domain if the multiplication of two non zero elements gives another non zero ... | |
| Abstract Algebra | 7/21/2008 |
| Q: Scott, I have an abstract algebra question. Given that componentwise addition of two elements in R^2 ... A: An isomorphism is an operation that when applied twice, the original obejct is gotten back. In ... | |
| Abstract Algebra | 7/21/2008 |
| Q: Scott, I have a question in abstract algebra. Given a and b are elements of group G. Prove that if ... A: In mathematics, an abelian group, also called a commutative group, is a group (G, * ) with the ... | |
| Trigonometry | 7/20/2008 |
| Q: simplify the following expressions so that they involve a function of only one angle A. sin 80*- sin ... A: What does the symbol */ mean? I would suspect the expressions to be [sin(80)- sin(10)]/[sin(80) + ... | |
| 9x9 table (1-81) | 7/19/2008 |
| Q: I have a quick Lesson-Preparation Q. fparents | |