# Trig Help

• April 17th 2006, 11:17 AM
Trig Help
can someone help me with prove this problem? :confused: I feel really stupid because I know it's easy but my brain is fried at the moment. Thanks! :D

Prove the identity.

secx-1/1-cosx=secx
• April 17th 2006, 11:19 AM
TD!
I assume there are some brackets missing...

$
\frac{{\sec x - 1}}
{{1 - \cos x}} = \frac{{\frac{1}
{{\cos x}} - 1}}
{{1 - \cos x}} = \frac{{\frac{{1 - \cos x}}
{{\cos x}}}}
{{1 - \cos x}} = \frac{1}
{{\cos x}} = \sec x
$
• April 17th 2006, 11:23 AM
Thank you very much. I understand it now.
• April 17th 2006, 11:25 AM
TD!
You're welcome.

In such problems, convert everything to the same trig function - if possible - and simplify. Like here, convert the given sec(x) to 1/cos(x) and do some algebraic simplifications (on the fraction).