SOLUTION: 9 cos ^3 x= 9 cos x

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Question 929646: 9 cos ^3 x= 9 cos x
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
9 cos ^3 x= 9 cos x [0,2π)
divide both sides by 9cosx
cos^2(x)=1
cosx=±√1=±1
cosx=1
x=0
cosx=-1
x=π