SOLUTION: cos^2-sin^2=2cos^2-1 prove that this is true

Question 169899: cos^2-sin^2=2cos^2-1 prove that this is true
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
cos^2-sin^2=2cos^2-1 prove that this is true
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Note: sin^2(x) = 1 - cos^2(x)
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Substitute that into the left side to get:
cos^2 -(1-cos^2) = 2cos^2-1
cos^2 -1 + cos^2 = 2cos^2-1
2cos^2 - 1 = 2cos^2 - 1
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Cheers,
Stan H.
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