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September 21, 2014

September 21, 2014

Posted by **chris** on Thursday, November 18, 2010 at 10:33pm.

- trig -
**Reiny**, Thursday, November 18, 2010 at 10:43pmdo you see the pattern

cos(A + B) = cosAcosB - sinAsinB here ?

also remember that cos(-A) = cos (A)

give it a try

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