# Inverse of a function

1. Sep 12, 2008

### Squeezebox

1. The problem

Find the inverse of F(x)= x/(x+1)

3. The attempt at a solution

I have no idea where to begin. Everything I have tried has just taken me back to the original equation.

2. Sep 12, 2008

### Defennder

There is a technique for finding an inverse of a function f(x), if it exists. Let y = f(x). Express x in terms of y to get x = g(y). Replace y with x and there's your inverse function.

3. Sep 12, 2008

This is similar to, but slightly more direct than, the method in the previous post.

$$y = \frac x {x+1}$$
$$x = \frac y {y+1}$$
Solve the second equation for $$y$$ in terms of $$x$$ - the result is the inverse function.