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1: Real and Hyperreal Numbers

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    155776
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    Chapter 1 takes the student on a direct route to the point where it is possible to study derivatives. Sections 1.1 through 1.3 are reviews of precalculus material and can be skipped in many calculus courses. Section 1.4 gives an intuitive explanation of the hyperreal numbers and how they can be used to find slopes of curves. This section has no problem set and is intended as the basis for an introductory lecture. The main content of Chapter 1 is in the last two sections, 1.5 and 1.6. In these sections, the student will learn how to work with the hyperreal numbers and in particular how to compute standard parts. Standard parts are used at the beginning of the next chapter to find derivatives of functions. Sections 1.5 and 1.6 take the place of the beginning chapter on limits found in traditional calculus texts.

    For the benefit of the interested student, we have included an Epilogue at the end of the book that presents the theory underlying this chapter.

    • 1.1: The Real Line
      Definition of real numbers and the real number line. Expansion of the real line to rectangular coordinate systems.
    • 1.2: Functions of Real Numbers
      Definition of real functions of one or two variables, domain, and range. Examples of some important basic functions, including the constant, identity, and absolute value functions.
    • 1.3: Straight Lines
      Definition of linear functions. Formats of equations for lines and methods of calculating these equations from given information.
    • 1.4: Slope and Velocity; The Hyperreal Line
      Average slopes along a curve; average velocity, given a function of distance as time. Introduction to hyperreal numbers and infinitesimals, and how they can be used to calculate slope of a curve at a point.
    • 1.5: Infinitesimal, Finite, and Infinite Numbers
      The Extension Principle and the Transfer Principle as rules for relating functions of real and hyperreal numbers. Definitions of and rules for infinitesimal, finite, and infinite numbers.
    • 1.6: Standard Parts
      Discussion of the standard part principle, which allows for the finding of the standard number infinitely close to any finite hyperreal number. Steps of this process for different formats of finite hyperreal numbers.
    • 1.7: Extra Problems for Chapter 1


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