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Expert: Scotto - 6/23/2009


Question
how do go by State the quadrant in which the angle terminates(is found) and state the value of the reference angle : (Remember, the reference angle is always measured with the x-axis !!!!!!)

1.   108°

2.   310°

3.    7π/5

4.   – 259°

5.    128°


Answer
The positive x axis is 0°, the positive y axis is 90°,
the negative x axis is 270°, and the negative y axis is 270°.
Also, you need to know that π radians is the same as 180°.
This means there are π/2 radians in an quadrant.

This makes the x axis also 360°.

Thak the trunc(angle/90°)+1,
and that will tell you the quadrant it is in.  

1. Note that trunc(108°/90°) + 1 = 1 + 1 = 2,
so it is in quadrant II.

2. Note that trunc(310°/90°) + 1 = 3 + 1 = 4,
so it is in quadrant IV.

3. Take 7π/5 and multiply by 180°/π to get degrees.
(7π/5)(180°/π) = (7*180/5)° = 7*36° = 252°.
Now if we take trunc(252°/90°) + 1, we get 3.
This means the angle is in quadrant III.

4. Note that -259° is that same if 360° is added to it.
360° - 259° = 101°.  trunc(101/90) + 1 = 2, so it is in quadrant II.

5. Note that trunc(128°/90°)+1 = 1+1 = 2.
This means that it is in the 2nd quadrant.  

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Scotto

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Any kind of calculus question you want. I also have answered some questions in Physics (mass, momentum, falling bodies), Chemistry (charge, reactions, symbols, molecules), and Biology.

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Experience in the area: I have tutored students in all areas of mathematics for over 25 years. Education/Credentials: BSand MS in Mathematics from Oregon State University, where I completed sophomore course in Physics and Chemistry. I received both degrees with high honors. Awards and Honors: I have passed Actuarial tests 100, 110, and 135.

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Maybe not a publication, but I have respond to well oveer 7,500 questions on the PC. Well over 2,000 of them have been in calculus.

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I aquired well over 40 hours of upper division courses. This was well over the number that were required. I graduated with honors in both my BS and MS degree from Oregon State University. I was allowed to jump into a few junior level courses my sophomore year.

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I have been nominated as the expert of the month several times. All of my scores right now are at least a 9.8 average (out of 10).

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My past clients have been students at OSU, students at the college in South Seattle, referals from a company, friends and aquantenances, people from my church, and people like you from all over the world.

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