# Calculators Help with Ti89

1. Nov 7, 2004

### Moose352

Either I'm lost, or my Ti89 has an error in it's CAS (which is unbelievable). What is the derivative of 1/(1-x) ?

2. Nov 7, 2004

### jamesrc

$$\frac 1 {(1-x)^2}$$

What does your calculator say it is?

3. Nov 7, 2004

### Moose352

Nevermind, i got it.