SOLUTION: Rewrite with only sin x and cos x. cos 2x - sin x

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Question 1063203: Rewrite with only sin x and cos x.
cos 2x - sin x
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
cos 2x - sin x
cos(2x)=1-2 sin^2 x
Therefore we have 1-2sin^2x-sinx
That is -(2sin^2 x+sin x-1)=-(2sin x-1)(sin x+1).
Not clear if that answers the question or whether both sin x and cos x have to be present.
cos (2x)=2 cos^2 x -1
Then it is 2 cos^2x -sin x-1