SOLUTION: Find f −1. f(x) = x/x+1 for x > −1

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Question 1116532: Find f −1.
f(x) = x/x+1 for x > −1
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
I'm assuming you mean the inverse(?).
Start with x,y definition,
y=x%2F%28x%2B1%29
Interchange x and y and solve for y.
This new y is the inverse of the original.
x=y%2F%28y%2B1%29
x%28y%2B1%29=y
xy%2Bx=y
xy-y=-x
y%28x-1%29=-x
y=-x%2F%28x-1%29
highlight%28y%5Binv%5D=x%2F%281-x%29%29