AP Precalculus Unit 1.1

A function is a mathematical relationship that map a set of input values to a set of outpu values.

Function Notation: When describing functions, we usually use the variables x and y. To write that y is a function of x, we would say y = f(x), where f represents the function.

Domain is the set of allowable input values

Range is the set of allowable output values

Function Definition: For every x in the domain, there can only be one and only one y in the range. Basically, no x value can repeat.

Expressing Functions:

• Verbally: Words are used to describe the relationship

• Graphically: A graph representing the function to describe the relationship

• Analytically: Using formula and equations