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December 21, 2014

December 21, 2014

Posted by **Maria** on Monday, March 19, 2012 at 7:38pm.

cos4x-cos2x=0

So,this is what i've done so far:

cos4x-cos2x=0

cos2(2x)-cos2x

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

No idea what to do next.

- Pre-Calculus -
**bobpursley**, Monday, March 19, 2012 at 8:10pmhttp://answers.yahoo.com/question/index?qid=20080413170208AAL5ESb

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