SOLUTION: cos-pi/12=

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Question 871595: cos-pi/12=
Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website!
cos(-pi/12) = cos(-15 deg( - cos(-30/2) = sqrt[(1-cos(30))/2]
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= sqrt[(1-(sqrt(3)/2)/2]
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= sqrt[(2-sqrt(3)/4] = (1/2)(2-sqrt(3)
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Cheers,
Stan H.
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