SOLUTION: Solve 2cos^2 - 5cos(x) +2 =0 for principal values of x. Express the solution(s) in degrees.

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Question 1032167: Solve 2cos^2 - 5cos(x) +2 =0 for principal values of x. Express the solution(s) in degrees.
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Solve 2cos^2 - 5cos(x) + 2 = 0 for principal values of x. Express the solution(s) in degrees.
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2cos^2 -4cos -cos + 2 = 0
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2cos(cos-2)-(cos-1) = 0
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(cos-2)(2cos-1) = 0
cos(x) = 2 or cos(x) = 1/2
Acceptable solution::
cos(x) = 1/2 implies x = 60 degrees
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Cheers,
Stan H.
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