I looked at the topics here and in other foruns, and they didn't answer my question.
I want find the inverse of a simple function like
f(x) = 2x + 1.
I know that f(x)^-1 is (x-1)/2 , but i couldn't calculate with Mathematica (i use the 8th version).
I tried to use Invert, InvertFunction, Solve and they haven't solved my problem.
Thanks (: .