SOLUTION: What is the terminal point of 7pie over 4

Algebra ->  Trigonometry-basics -> SOLUTION: What is the terminal point of 7pie over 4      Log On


   

Question 975223: What is the terminal point of 7pie over 4
Answer by farohw(175) About Me  (Show Source):
You can put this solution on YOUR website!

Most Pre-calculus(Alg/Trig) and Calculus textbooks will have the unit circle with quadrants, angles and terminal points either in the back or front of the book for reference.

If not, convert radians to degrees by multiplying %28%287pi%29%2F4%29%2A%28180%2Fpi%29+=+315+deg which is in Quadrant IV of the unit circle.

To find the reference angle: 360 - 315 = 45 degrees is equivalent to pi%2F4 with (cos,sine) values of cos%28pi%2F4%29+=+sqrt%282%29%2F2, sine%28pi%2F4%29+=+sqrt%282%29%2F2.

Since we are in Quadrant IV sine will be negative cos%287pi%2F4%29+=+sqrt%282%29%2F2 and sine%287pi%2F4%29+=+-sqrt%282%29%2F2.

The terminal point is P(x,y) = sqrt%282%29%2F2, -sqrt%282%29%2F2.



Best,
Farohw