# Math Help - functions and inverses

1. ## functions and inverses

f(x) = 2x
x-5

I need to determine the domain and range for f(x). I know that the domain is not equal to 5, but I'm not sure on how to find the range. I think it is all real numbers.

From this one problem, I have to also find the inverse. I came up with:

f(x) = -25x-2
10

But I don't think it is right.

Any help would be great thanks!

2. Yes the domain is all real numbers excluding 5 and the range is all real numbers. What does f(x) graph? That will help you be assured about your answers. You are right though.

To find the inverse of f(x), switch the x's and y's and solve for y. So if you had $f(x)=\frac{2x}{x-5}$, then write $x=\frac{2y}{y-5}$ and solve for y.