You can use this applet to get an idea at what sums, products, differences, quotients, and compositions of two functions are, and what inverses of functions look like.

You can enter two functions the usual way, and look at all these things by selecting them. I find looking at more than one at a time confuses me, and looking at all at once drives me nuts.

This tool uses JQWidgets extensively. Please verify their copyright.

Developed by Daniel Kleitman and Jean-Michel Claus.