SOLUTION: If cosθ = -3/5, find cos(pi/2 - θ). Write your answer as a fraction.

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Question 1187340: If cosθ = -3/5, find cos(pi/2 - θ). Write your answer as a fraction.
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

If cos%28theta%29=-3%2F5=> adj=-3 and hyp=5
then
opp=sqrt%285%5E2-%28-3%29%5E2%29
opp=sqrt%2816%29
opp=4 or opp=-4
so, sin%28theta%29=4%2F5 or sin%28theta%29=-4%2F5
since cos%28pi%2F2-theta%29=sin%28theta%29, we have
cos%28pi%2F2-theta%29=4%2F5 or cos%28pi%2F2-theta%29=-4%2F5