SOLUTION: Find the exact value of sin (7Pi / 2)

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Question 316691: Find the exact value of sin (7Pi / 2)
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
pi radians = 180 degrees
pi%2F2 radians = 90 degrees
%287%2Api%29%2F2 radians = 90 + 90 + 90 + 90 + 90 + 90 + 90 = 630 degrees
630%2F360 = 1 3/4
This is a complete turn from 0 degrees back to 0 degrees and
then a 3/4 turn
This is the same as -90 degrees
sin%28-90%29+=+-1