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4: The Integral

  • Page ID
    212030
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    Previous chapters dealt with differential calculus. They started with the “simple” geometrical idea of the slope of a tangent line to a curve, developed it into a combination of theory about derivatives and their properties, examined techniques for calculating derivatives, and applied these concepts and techniques to real-life situations. This chapter begins the development of integral calculus and starts with the “simple” geometric idea of area— an idea that will spawn its own combination of theory, techniques and applications.

    One of the most important results in mathematics, the Fundamental Theorem of Calculus, appears in this chapter. It unifies differential and integral calculus into a single grand structure. Historically, this unification marked the beginning of modern mathematics, and it provided important tools for the growth and development of the sciences.

    The chapter begins with a look at area, some geometric properties of areas, and some applications. First we will examine ways of approximating the areas of regions such as tree leaves bounded by curved edges and the areas of regions bounded by graphs of functions. Then we will develop ways to calculate the areas of some of these regions exactly. Finally, we will explore the rich variety of uses of “areas.”


    4: The Integral is shared under a not declared license and was authored, remixed, and/or curated by LibreTexts.

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