Functional Notation *---*

Function Notation is just using a symbol such as f(x) =, as another way to represent y.
Simply all that is needed is for evaluating each function is substitution.

For example:

(the arrow is read "is mapped to")

(the vertical bar is read "such that")

So using an equation f(x) = x² + 7


Find f(3).

To find f(3) replace x with 3.

f(3) = (3)² + 7

The answer is 16.
Courtesy of http://www.regentsprep.org/Regents/math/algtrig/ATP5/EvaluatingFunctions.htm