# Finding the limit

1. Oct 3, 2010

### screamtrumpet

lim (2-x)/(x^2-4)
x>2

Find the limit(is it exists)

The substitution method failed so I factored the bottomto (x+2)(x-2).Where do I go from here?
1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

2. Oct 3, 2010

### HallsofIvy

A very important but often overlooked "law of limits":

If f(x)= g(x) for all x except x= a, then $\displaytype\lim_{x\to a}f(x)= \lim_{x\to a} g(x)$.

Here, for all x except x= 2, (2- x)/(x-2)(x+2)= -1/(x+2).

3. Oct 3, 2010

### Oerg

use l'Hospital's rule

4. Oct 3, 2010

Thank you