SOLUTION: cos( 2theta - Pi/2)= 1/2

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Question 425631: cos( 2theta - Pi/2)= 1/2
Answer by htmentor(1343) About Me  (Show Source):
You can put this solution on YOUR website!
Using the trigonometric identity, cos%28A-pi%2F2%29+=+sin%28A%29, with A=2theta
So we are left with sin%282theta%29+=+1%2F2 -> 2theta+=+arcsin%281%2F2%29
2theta = 30 degrees, or theta = 15 degrees = 15%2Api%2F180%29 = 0.2618 radians