Finding the Inverse Function of F(x) = x/(x+1)

Skizye
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Homework Statement


If F(x) = \frac{x}{x + 1}, then the inverse function, f^{-1}, is given by f^{-1}(x) =

Homework Equations


The Attempt at a Solution


I've replaced F(x) with y, and switched the x and y variables. Where I'm having a problem is solving the resulting equation, here's what I've done so far.

x = \frac{y}{y + 1},

xy + x = y,

x(y + 1) = y,

but as far as I can tell that just takes me back to where I started.

Also, I believe this is a question from an old AP Calculus exam. It's technically homework from a calculus class but seems to primarily involve algebra. Did I put it in the right forum or should it have gone in the precalculus forum? Thanks!
 
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Go back to xy + x = y, gather the y values together, then solve.
 
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