There is an algebra test to see if two functions are inverses of each other.  But, before I can tell you about it, I need to show you this stuff first.

This notation we know:

And we think of it as:

Now, we're going to have two functions to mess with at once...  Like these:

and

The game is that we'll need to find

That's f of g(x).

If you read it and say it correctly, it's really going to help you do the problem!

Before, we had f(x) which we read as "f of x"...

Now, we have f(g(x))...

f of g(x)

Same game...  Just a bigger blob!