document.write( "Question 936229: How can I prove this?
\n" ); document.write( "cos^2(x)-sin^2(x)=1+sin(x)*cos(x) \n" ); document.write( "

Algebra.Com's Answer #570049 by tommyt3rd(5050) $\"\"$ $\"About$

You can put this solution on YOUR website!
you cannot - it's not an identity \n" ); document.write( "

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