Intermediate Algebra/Relations and Functions

Relations and Functions

Relations and Functions can be compared to machines. You perform operations on an input, or domain, and receive a certain output, or range.

The difference between functions and relations is that with functions, you always enter an input, and receive one and only one output. For example, the relation $f(x)=2x+1$ is a function because if I entered any number, I would always get a different output.

You can evaluate functions for values. Using the previous example, if you had x = 2, then

$f(2)=2(2)+1$
$f(2)=4+1$
$f(2)=5$