# Need help with a proof

• December 1st 2012, 10:50 AM
kyle0671
Need help with a proof
Been trying to do this proof for a while and I can't seem to solve it:
Solve by using pythagorean identities:

sinx/1-cosx + sinx/1+cosx = 2cscx

Help much appreciated.
• December 1st 2012, 10:57 AM
Scopur
Re: Need help with a proof
Ill get you started

LHS:
$\sin(x) \left ( \frac{1}{1-\cos(x)} + \frac{1}{1+\cos(x)} \right)$

$\sin(x) \left [ \frac{1+\cos(x) + 1 -\cos(x)}{(1-\cos(x))(1+\cos(x))} \right]$

Don't forget the most important trig identity
$\sin(x)^2 + \cos(x)^2 = 1$
• December 1st 2012, 01:30 PM
kyle0671
Re: Need help with a proof
Thanks for the help. Got it solved