Equations as Functions

• Functions can also be represented by an equation (or rule).

• The equations will generate ordered pairs by taking an input that results in a certain output.

• The graph of an equation is the set of all its ordered pairs, which often forms a line or a curve.

Example Functions

• Think of a Function like a machine that takes an x-value and produces a y-value.

• The x-value is called the independent variable (because you pick it!)

• The y-value is called the dependent variable because its value will depend on the value of x.

Domain and Range

• X represents the elements of the Domain (input). Therefore your x-values are your domain.

• Y represents the elements of the Range (output). Therefore your y-values are your range

Function Notation

• Equations that represent functions are often written in Function Notation

• You read Function Notation as "f of x equals..."

• f(x) is the output and x is the input.

Evaluating Functions

Function Notation is especially useful for finding a value in the range that corresponds to a certain domain value.