(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

All right, so I was trying to help a friend prove a certain (complicated) trig identity for summer homework, but I got stuck myself... hopefully one of you will be able to help.

The trig identity in question is...

[tex]\frac{cos(x)}{1-tan(x)} + \frac{sin(x)}{1-cot(x)} = cos(x) + sin(x)[/tex]

2. Relevant equations

1+tan^2(x)=sec^2(x)

1+cot^2(x)=csc^2(x)

3. The attempt at a solution

So far I've gotten it to...

[tex]\frac{cos(x)-sin(x)}{sec^2(x)-2tan(x)} - \frac{cos(x)-sin(x)}{csc^2(x)-2cot(x)} = cos(x)+sin(x)[/tex]

But although I think that's a really nice form (two very similar terms), I have no idea where to go from there. Could one of you help me out?

**Physics Forums | Science Articles, Homework Help, Discussion**

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Homework Help: Tricky Trig Problem

**Physics Forums | Science Articles, Homework Help, Discussion**