this section. Mathematicians, like myself, think of functions as anything that returns an output based on an input. Students, like yourself, think of a function as anything that looks like f(x) = .... Somewhere in the middle we will meet but keep in mind functions are more general than you probably think.

Okay that said, the most difficult thing about functions is just getting used to the notation. To those in the know, this is simple, for those learning it seems hard. If you don't know, pay special attention to example 3 and example 9.

In this section you also learn some language about functions: The domain and range. If you think of a function taking an input and returning an output (like I do) then the domain is all possible inputs and the range is all possible outputs. If you think of a function as f(x) = ... then the domain is all x's that work and the range is all values that f(x) can be. In the next section, there will be an interpretation in terms of the graph. In this class, I won't emphasize these two concepts.