Posted by **Josh** on Thursday, February 23, 2012 at 9:46pm.

Solve Cos^2(x)+cos(x)=cos(2x). Give exact answers within the interval [0,2π)

Ive got the equation down to -cos^2(x)+cos(x)+1=0 or and it can be simplified too sin^2(x)+cos(x)=0

If you could tell me where to go from either of these two, it would be great help.. Thankyou for any responses

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