Prentice Hall Algebra 2

The degree of a polynomial function affects the shape of its graph and determines the maximum number of turning points, or places where the graph changes direction. It also affects the end behavior, or the directions of the graph to the far left and to the far right.

For polynomial functions of degree one or greater, there are four types of end behavior as you move to the left and move to the right, away from the origin: up and up, down and down, down and up, and up and down.

Up and Up Down and Down Down and Up Up and Down
A w-shaped graph has ends rising leftward and rightward in quadrant 2 and 1. This is up and up behavior. A downward-opening parabola has ends falling leftward and rightward in quadrant 3 and 4. This is down and down behavior. An s-shaped curve falls leftward through quadrant 3 from the origin. It levels out through the origin, and then rises rightward through quadrant 1. This is down and up behavior. An N-shaped curve rises leftward through quadrant 2 from a vertex in quadrant 3. From the vertex in 3, it also rises rightward through the origin to a vertex in quadrant 1, and then falls rightward through quadrant 4. This is up and down behavior.
y equals , x to the fourth , minus , 3 x cubed , plus 5 x y equals negative , x squared , plus 6 x y equals , x cubed y equals negative 0 . 3 , x cubed , plus 4 x plus 2

You can determine the end behavior of a polynomial function of degree n from the leading term eh x to the n  of the standard form.

End Behavior of a Polynomial Function of Degree n With Leading Term eh x to the n  (Moving Away From the Origin)
  n Even n Odd
a Positive Up and Up Down and Up
a Negative Down and Down Up and Down

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Table of Contents

Prentice Hall Algebra 2 Chapter 1 Expressions, Equations, and Inequalities Chapter 2 Functions, Equations, and Graphs Chapter 3 Linear Systems Chapter 4 Quadratic Functions and Equations Chapter 5 Polynomials and Polynomial Functions Chapter 6 Radical Functions and Rational Exponents Chapter 7 Exponential and Logarithmic Functions Chapter 8 Rational Functions Chapter 9 Sequences and Series Chapter 10 Quadratic Relations and Conic Sections Chapter 11 Probability and Statistics Chapter 12 Matrices Chapter 13 Periodic Functions and Trigonometry Chapter 14 Trigonometric Identities and Equations Skills Handbook English/Spanish Illustrated Glossary Selected Answers Index Acknowledgments