What is a function?

f(8) = 21 When you input 8 into the function the only output is 21.

Evaluate the following for the given domain f(x) = 3(x - 1)

The graph is a function.

Is the graph a function or not?

The mapping is Not a function.

Is the mapping a function or not?

The ordered pair is NOT a function.

Is the ordered pair a function or not {(4,3) , (10, -1) , (2, 9) , (4, 8) , (-6, 0)}?

Function Notation

A method of writing functions. f(x) is the same as y, and is read 'f of x'. It is NOT f multiplied by x. The 'f' is the name of the function and can be any letter except x or y. The 'x' is the input variable.

f(0) = 5. When you input 0 into the function the only output is 5.

Evaluate the following for the given domain f(x) = 2x + 5

2, 8, 9, 12

Name the domain from the following ordered pairs; {(2,5) (2,8) (8, 12) (9, 13) (12, 8)}.

5, 8, 12, 13, 8

Name the range from the following ordered pairs; {(2,5) (2,8) (8, 12) (9, 13) (12, 8)}.

Domain

The set of input (x) values of a function.

Range

The set of output (y) values of a function.

Vertical Line Test

Use to determine if a graph is a function. If vertical line and function intersect at most one time, then it's a function. If there is more than one intersection, then it's not a function.

function

a relationship or expression involving one or more variables