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3: Polynomial Functions

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• 3.1: Graphs of Polynomials
Three of the families of functions studied thus far: constant, linear and quadratic, belong to a much larger group of functions called polynomials. We begin our formal study of general polynomials with a definition and some examples.
• 3.2: The Factor Theorem and the Remainder Theorem
Suppose we wish to find the zeros of an arbitrary polynomial. Even though we could use the 'Zero' command to find decimal approximations for these, we seek a method to find the remaining zeros exactly. The point of this section is to generalize the technique applied here. First up is a friendly reminder of what we can expect when we divide polynomials.
• 3.3: Real Zeros of Polynomials
This section presents results which will help us determine good candidates to test using synthetic division. There are two approaches to the topic of finding the real zeros of a polynomial. The first approach (which is gaining popularity) is to use a little bit of Mathematics followed by a good use of technology like graphing calculators. The second approach (for purists) makes good use of mathematical machinery (theorems) only. For completeness, we include both approaches.
• 3.4: Complex Zeros and the Fundamental Theorem of Algebra
Previously, we were focused on finding the real zeros of a polynomial function. In this section, we expand our horizons and look for the non-real zeros as well. The requires introducing the imaginary unit, i, that while not a real number, plays along well with real numbers, and acts very much like any other radical expression
• 3.E: Polynomial Functions (Exercises)
These are homework exercises to accompany Chapter 3 of Stitz and Zeager's "Pre-Calculus" Textmap.

Contributors

• Carl Stitz, Ph.D. (Lakeland Community College) and Jeff Zeager, Ph.D. (Lorain County Community College)