SOLUTION: how do you solve cos^2x-sin^2x+cosx=0 for 0<x<180

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Question 614968: how do you solve cos^2x-sin^2x+cosx=0 for 0
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
how do you solve cos^2x-sin^2x+cosx=0 for 0
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Domain:(0,2π)
cos^2x-sin^2x+cosx=0
cos^2x-(1-cos^2x)+cosx=0
cos^2x-1+cos^2x+cosx=0
2cos^2x+cosx-1=0
(2cosx-1)(cosx+1)=0
2cosx-1=0
cosx=1/2
x=π/3,5π/3
or
cosx+1=0
cosx=-1
x=π