SOLUTION: If 0 degrees less than or equal to x degrees less than or equal to 180 degrees and 4cos^2x=1,then x degrees=?

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Question 633753: If 0 degrees less than or equal to x degrees less than or equal to 180 degrees and 4cos^2x=1,then x degrees=?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
If 0 degrees less than or equal to x degrees less than or equal to 180 degrees and 4cos^2x=1,then x degrees=?
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cos^2(x) = 1/4
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cos(x) = +1/2 or cos(x) = -1/2
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x = pi/3 or x = (2/3)pi
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Cheers,
Stan H.
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