SOLUTION: If cos theta = -3/5, fund cos 2 theta and express in simplest form.

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Question 1030116: If cos theta = -3/5, fund cos 2 theta and express in simplest form.
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
: If cos theta = -3/5, fund cos 2 theta and express in simplest form.
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cos(2t) = cos^2(t) - sin^2(t) = 2cos^2(t)-1 = 2(9/25)-1 = -7/25
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Cheers,
Stan H.
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