2.3 Functions and Relations

Miller & Gerken, College Algebra 2e — Pages 222-239

Learning Objectives

  • Determine if a relation is a function

  • Apply the vertical line test

  • Find domain and range

  • Use function notation

Key Concepts

Function Definition

A function is a relation where each input has exactly one output.

Vertical Line Test

A graph represents a function if no vertical line intersects it more than once.

Function Notation

\[f(x) = \text{expression in } x\]

\(f(a)\) means "evaluate the function at \(x = a\)"

Domain and Range

Domain

All valid input values (\(x\))

Range

All possible output values (\(y\) or \(f(x)\))

Examples

Example 1. Example 1

Work through textbook example…​

Practice Problems

Problem 1 (p. XX, #YY)

Problem:

My Work:

Answer:

Section Summary

  1. Key point 1

  2. Key point 2

Study Notes

Personal observations…​