February 21, 2017

Homework Help: Precalculus

Posted by Greg on Wednesday, November 14, 2012 at 3:07pm.

Prove or disprove cos(x+y)cos(x-y)=cos squared (x) - Sin squared (x)

I dstributed the cosines and attempted to cancel out terms but I can't get the signs right. Any help on what I am missing?

Answer This Question

First Name:
School Subject:

Related Questions

More Related Questions