SOLUTION: Solve: 4cos^2x-4cosx+1=0

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Question 1065693: Solve:
4cos^2x-4cosx+1=0
Found 2 solutions by KMST, Boreal:
Answer by KMST(5328) About Me  (Show Source):
You can put this solution on YOUR website!
4u%5E2%2B4u%2B1=%282u%2B1%29%5E2 as you knew from factoring polynomials.
Now, re-write that with cos%28x%29 instead of u .

Factoring polynomials will follow you for as long as you have a math course.
It does not matter if you are studying trigonometry or calculus,
you cannot forget factoring.

Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
4cos^2x-4cosx+1=0
(2 cos x -1)^2=0
2 cos x=1
cos x=(1/2)
This is (1/2) at pi/3 radians and at 5 pi/3 radians.