Review of Basic Functions

From the last module you learned that:

1. Functions express a one-to-one relation between an independent variable x and
   a dependent value f(x) (or y).
2. The y = notation can be replaced by the f(x) = notation to express the same information.
3. You can use f(0), f(1) notation to show what values are generated when these numbers are substituted into a function or equation.

For example:

If f(x) = x² + 2x, then

f(2) = 2² + 2•2 = 8
f(1) = 1² + 2•1 = 3
f(0) = 0² + 2•0 = 0

f(-3) = (-3)² + 2•(-3)
        = 9 - 6
        = 3