# Limits at infinity of trigometric function

1. Sep 17, 2010

### Willian93

1. The problem statement, all variables and given/known data

lim (x→pi)〖sin(x-pi)/(x-pi)〗

2. Relevant equations

i dont know if we should use trig identity

sin(a-b)= sinA cos B- CosA sin B

3. The attempt at a solution
i use identities to solve that, i did not get the answer. i tried to multiply by conjugate, did not work also.

Last edited: Sep 17, 2010
2. Sep 17, 2010

### vela

Staff Emeritus
You could use a substitution, u = x - $\pi$, and that limit should be familiar.