SOLUTION: Verify the following identity by using an angle sum identity: cos(2x) = 1 – 2(sin^2x). Hint (2x = x + x)

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Question 890660: Verify the following identity by using an angle sum identity:
cos(2x) = 1 – 2(sin^2x). Hint (2x = x + x)
Found 2 solutions by Alan3354, stanbon:
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Verify the following identity by using an angle sum identity:
cos(2x) = 1 – 2(sin^2x). Hint (2x = x + x)
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Wow, helpful hint.
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cos(A + B) = cos(A)cos(B) - sin(A)sin(B)

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Verify the following identity by using an angle sum identity:
cos(2x) = 1 – 2(sin^2x). Hint (2x = x + x)
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cos(2x) = cos(x+x) = cos^2(x) -sin^2(x) = 1-sin^2(x)-sin^2(x) = 1-2sin^2(x)
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Cheers,
Stan H.