SOLUTION: cos^2theta - cos theta = 0 I don't understand how to solve this and how to do the work.

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Question 1034869: cos^2theta - cos theta = 0
I don't understand how to solve this and how to do the work.
Found 2 solutions by harpazo, ikleyn:
Answer by harpazo(655)   (Show Source):
You can put this solution on YOUR website!
cos^2 θ - cos θ = 0
Factor out cos θ.
cos θ(cos θ - 1) = 0
Set each factor to 0 and solve for θ.
cos θ = 0
θ = pi/2, 3pi/2
cos θ - 1 = 0
cos θ = 1
θ = 2pi

Answer by ikleyn(52908)   (Show Source):
You can put this solution on YOUR website!
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