# Thread: Assistance with a proof

1. ## Assistance with a proof

I'm having trouble proving the following:

(sinx/sinx + cosx) + (cosx/sinx - cosx) = 1/ 2sin^2x - 1

I can get the numerator to become 1 on the left side but am having trouble with the denominator.

Can someone help?

2. ## Re: Assistance with a proof

$\displaystyle {\sin^2(x)+\cos^2(x)=1 \implies 2\sin^2(x)+\cos^2(x)=1+\sin^2(x)\implies \sin^2(x)-\cos^2(x)=2\sin^2(x)-1}$