SOLUTION: prove that cos 30 cos 30 - 1 = cos 60
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Question 971659: prove that cos 30 cos 30 - 1 = cos 60
Answer by Alan3354(69443) (Show Source): You can put this solution on YOUR website!
prove that cos 30 cos 30 - 1 = cos 60
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cos(30) = sqrt(3)/2
cos^2(30) = 3/4
3/4 - 1 = -1/4
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cos(60) = 1/2
They're not equal.
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