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April 24, 2014

April 24, 2014

Posted by **Anonymous** on Monday, November 2, 2009 at 12:04pm.

a) cos2x = 1 - 2sin^2x

b) cos2x = 2cos^2x - 1

- advanced functions -
**bobpursley**, Monday, November 2, 2009 at 1:01pmsin^2x+ cos^2x=1

cos^2x+ sin^2x-2sin^2x=1-2sin^2x

cos^2x-sin^2x=1-2sin^2x

cos(2x)=1-2sin^2x

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