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

Question 1150647: solve the equation

cos theta = -sin(-theta)
Answer by Alan3354(69443) (Show Source): You can put this solution on YOUR website!
cos theta = -sin(-theta)
============
sin(-t) = -sin(t)
---> cos(t) = sin(t)
---
theta = 45, 225 degs + n*360, n = integer (we all know that)
=================
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

t = 45

225
etc

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