SOLUTION: Find all solutions of theta 2cos^2{theta}-3cos{theta}=-1

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Question 64561: Find all solutions of theta
2cos^2{theta}-3cos{theta}=-1
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
2cos^2{theta}-3cos{theta}+1=0
(2cos(theta)-1)(cos(theta)-1)=0
2cos(theta)=1 or cos(theta)-1=0
cos(theta)=1/2 or cos(theta)=1
theta=pi/3 or -pi/3 or theta=pi/4 or (5/4)pi
There are more solutions if you throw in the plus and - 2pi's
Cheers,
Stan H.