# Inverse of a function

1. Mar 18, 2007

### danago

Hi. The question wants me to find the inverse of $$y = \frac{{x - 1}}{{x - 2}}$$

Heres my working for it:
$$\begin{array}{l} x = \frac{{y - 1}}{{y - 2}} \\ xy - 2x = y - 1 \\ xy - y = 2x - 1 \\ (x - 1)y = 2x - 1 \\ y = \frac{{2x - 1}}{{x - 1}} \\ \end{array}$$

The answer says something different though.

If anybody could please tell me where im going wrong, or perhaps if the answer book is wrong, id greatly appreciate it.

Thanks,
Dan.

2. Mar 18, 2007

### danago

Ahh nevermind sorry.

My stupid mistake. The answer said $$y = \frac{{1 - 2x}}{{1 - x}}$$ which i just realised is exactly the same thing.

Thanks anyway :)