SOLUTION: solve the equation cos theta = -sin(-theta)

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Question 1150647: solve the equation

cos theta = -sin(-theta)
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
cos theta = -sin(-theta)
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sin(-t) = -sin(t)
---> cos(t) = sin(t)
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theta = 45, 225 degs + n*360, n = integer (we all know that)
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A more rigorous approach:
sin(-t) = -sin(t)
---> cos(t) = sin(t)
cos^2 = sin^2
1 - sin^2 = sin^2
sin^2 = 1/2
sin%28t%29+=+sqrt%282%29%2F2%29
t = 45
sin%28t%29+=+-sqrt%282%29%2F2%29
225
etc