SOLUTION: Cos^2 x=2-cosx Solve the equation for all real values of x

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Question 854411: Cos^2 x=2-cosx
Solve the equation for all real values of x
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Cos^2 x=2-cosx
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cos^2 + cos - 2 = 0
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Factor:
(cos+2)(cos-1) = 0
cos = -2 (extraneous)
OR
cos = 1
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x = arccos(1) = 0 degrees or 0 radians
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cheers,
Stan H.
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