SOLUTION: If 0 < A < 90 degrees, prove geometrically that cos(A-90°) = sinA

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Question 1151437: If 0 < A < 90 degrees, prove geometrically that cos(A-90°) = sinA
Answer by ikleyn(52790) About Me  (Show Source):
You can put this solution on YOUR website!
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For it, draw the unit circle in a coordinate plane, mark the angle A in it and then use definitions of sine and cosine.