SOLUTION: given that sin pi/8 = 0.38268, use identites to find cos pi/8

SOLUTION: given that sin pi/8 = 0.38268, use identites to find cos pi/8

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Question 607195: given that sin pi/8 = 0.38268, use identites to find cos pi/8
Answer by jim_thompson5910(35256) (Show Source): You can put this solution on YOUR website!
Hint: use the idea that $\sin^2(x) + \cos^2(x) = 1$ . We can solve for cosine to get $\cos(x) = \pm\sqrt{1-\sin^2(x)}$

Note: the sign of the result will depend on which quadrant the angle lies.
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