SOLUTION: Why is sin(-17π/4) evaluated to -1/√2 I keep getting the answer -√2/2 how would I evaluate cos(163π)? Thank you

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Question 923300: Why is sin(-17π/4) evaluated to -1/√2 I keep getting the answer -√2/2
how would I evaluate cos(163π)?
Thank you
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Why is sin(-17π/4) evaluated to -1/√2 I keep getting the answer -√2/2
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1%2Fsqrt%282%29+=+sqrt%282%29%2F2
They're the same.
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how would I evaluate cos(163π)?
163pi = 81*(2pi) + pi
--> cos(pi) = -1