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Homework Help: Inverse of a function

  1. Sep 12, 2008 #1
    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. jcsd
  3. Sep 12, 2008 #2

    Defennder

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    Homework Helper

    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.
     
  4. Sep 12, 2008 #3

    statdad

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    Homework Helper

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

    Start with your function.

    [tex]
    y = \frac x {x+1}
    [/tex]

    Interchange the variables.

    [tex]
    x = \frac y {y+1}
    [/tex]

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