SOLUTION: we are suppose to evaluate sin(3/4)pie

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Question 417424: we are suppose to evaluate
sin(3/4)pie
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!
sin%283%2F4%29%2Api+=+135 degrees

135 deg. lies in the 2nd quadrant

little more:

It is the same as 45+deg, but a reference angle.

sin%2845%29=+leg%2Fhyp+=+1%2Fsqrt%282%29=+sqrt%282%29%2F2

cos%2845%29=1%2Fsqrt%282%29=+sqrt%282%29%2F2

But in the second quadrant highlight%28sine%29ispositive and highlight%28cosine%29 is negative




so, sin%283%2A+pi%2F4%29+=+1%2Fsqrt%282%29=sqrt%282%29%2F2
cos%283+%2Api+%2F4%29+=+-1%2Fsqrt%282%29=-sqrt%282%29%2F2}


This will summarizes all:
Quadrant I: 0 to 90 degrees = 0 to p/2 radians
Quadrant II: 90 to 180 degrees = p/2 to p radians
Quadrant III: 180 to 270 degrees = p to 3p/2 radians
Quadrant IV: 270 to 360 degrees = 3p/2 to 2p radians
where p = 3.14 rounded to 2 decimal places.