Algebra/algebra

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Question
QUESTION: For f(x)=x+3 and g(x) =2x+5, find the following
a. (fog)(x)=
b. (gof)(x)=
c. (fog)(-1)=

ANSWER: What I believe that symbol is the same as is (fog)(x) = f(g(x)).
Is that correct?
This means we have
a. f(g(x)) = g(x) + 3, so it is 2x + 5 + 3 = 2x + 8.
b. g(f(x)) = 2*f(x) + 5 = 2(x+3) + 5 = 2x + 6 + 5 = 2x + 11.
c. f(g(-1) = f(2(-1)+5) = f(-2+5) = f(3) = 3+3 = 6.



---------- FOLLOW-UP ----------

QUESTION: Evaluate the function at the given values of the independent variable and simplify.
f(x)=4xsquare2-1/x2
a. f(3)
b. f(-3)
c. f(-x)

Answer
If that suppose to be 4x-1/x?
That is, are both x's squared?

a. Put in 3 as x and get 4*9 - 1/9 = 323 8/9.
b. Put in -3 as x and get the same thing,  since when squared the -3 still gives a 9.
c. When putting in a negative the answer is  the equation 4x-1/x since a negative squared is still positive.  That is, x = (-x).

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Scott A Wilson

Expertise

Any algebraic question you've got. That includes question that are linear, quadratic, exponential, etc.

Experience

I have solved story problems, linear equations, parabolic equations. I have also solved some 3rd order equations and equations with multiple variables.

Publications
Documents at Boeing in assistance on the manufacturiing floor.

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MS at math OSU in mathematics at OSU, 1986. BS at OSU in mathematical sciences (math, statistics, computer science), 1984.

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Both my BS and MS degrees were given with honors.

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Students in a wide variety of areas since the 80's; over 1,000 of them have been in algebra.

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