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2: Linear and Quadratic Functions

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    119148
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    • 2.1: Linear Functions
      We now begin the study of families of functions. Our first family, linear functions, are old friends as we shall soon see. Recall from Geometry that two distinct points in the plane determine a unique line containing those points.
    • 2.2: Absolute Value Functions
      There are a few ways to describe what is meant by the absolute value |x| of a real number x. The long and short of both of these procedures is that |x| takes negative real numbers and assigns them to their positive counterparts while it leaves positive numbers alone. This last description is the one we shall adopt, and is summarized and discuss in this Module.
    • 2.3: Quadratic Functions
      You may recall studying quadratic equations in Intermediate Algebra. In this section, we review those equations in the context of our next family of functions: the quadratic functions.
    • 2.4: Inequalities with Absolute Value and Quadratic Functions
      In this section, not only do we develop techniques for solving various classes of inequalities analytically, we also look at them graphically. The first example motivates the core ideas.


    This page titled 2: Linear and Quadratic Functions is shared under a CC BY-NC-SA 3.0 license and was authored, remixed, and/or curated by Carl Stitz & Jeff Zeager via source content that was edited to the style and standards of the LibreTexts platform.