Inverse of F(x)= x/(x+1): How to Find the Inverse Function | Step-by-Step Guide

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To find the inverse of the function F(x) = x/(x+1), start by letting y = F(x). Interchange the variables to get x = y/(y+1). Next, solve this equation for y in terms of x to determine the inverse function. This method is a straightforward approach to finding the inverse, ensuring that the original equation is transformed correctly. The final result will yield the inverse function needed.
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1. The problem

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


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

Start with your function.

<br /> y = \frac x {x+1}<br />

Interchange the variables.

<br /> x = \frac y {y+1}<br />

Solve the second equation for y in terms of x - the result is the inverse function.
 
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