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# C3 Inverse functions help watch

1. How do i do the inverse of f(x)=2/(x+1)
How do i do the inverse of f(x)=2/(x+1)
Name f(x) as y. Next change the x into y and the y into x. Rearrange the equation to make y the subject of the equation and then change y to f^-1 (x ), i,e. the inverse of f(x).
Hope this helps!

Post your answer or step by step working to make sure you understand!
3. One of the easiest ways of doing this is saying let f(x)=y
So now y=2/(x+1)
Now swap the x's and the y's so the x=2/(y+1). Now solve for y
So y+1 = 2/x. Now y=2/x - 1
So f^-1 (x) = 2/x - 1. Always remember to replace the y with f^-1 (x).
You could manipulate this to give f^-1(x) = (2-x)/x
When I put f^-1(x) I don't mean 1/f(x) I mean the inverse of f(x), Just to clarify.
Also remember that the inverse function is the reflection of the function in the line y=x.

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Updated: September 10, 2015
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