if f(x)=2x-4, find f^-1(x)

Question

anonymous · Answer

Hi Welcome to Openstudy!

Let f(x) = y
y=2x-4

you are looking for the inverse function
so you have to switch y and x
you will have
x=2y-4

now can you arrange this equation and solve for y?

mathmale · Answer

Borrowing from DataLG's suggestions:

1.  Let f(x)=y=2x-4; focus on y=2x-4

you are looking for the inverse function
2.  Interchange x and y ("so you have to switch y and x")
you will have (obtain)
x=2y-4

3.  Solve this x=2y-4 for y

now can you re-arrange this equation to solve for y?

4.  Replace that y with $$f ^{-1}(x)$$    This is the proper notation for "inverse function of f(x)".

mathmale · Answer

@berbabii:  Please write your answer here:$$f ^{-1}(x)=?$$