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Chapter 4


                                             Applied Maximum and

                                                                         Minimum














                               Optimization problems are one of the most important applica-
                               tions of differential calculus. Whether we are concerned with
                               how to get from A to B in the least amount of time, or we wish
                               to construct a box of maximum volume for a given amount of
                               material, we are looking for the “best” way to perform a given
                               task.
                                   The problem of optimization generally reduces to the
                               problem of finding the maximum or minimum value of a func-
                               tion subject to a given set of conditions or constraints. In this
                               chapter we will discuss how to set up a maximum/minimum
                               problem and solve it to find the optimal solution.
                                   We begin by reviewing a few basic definitions and
                               theorems.


                                A function f has an absolute maximum on an interval I
                                if there exists a number c in I such that f (x) ≤ f (c) for all
                                 x in I.


                               A similar definition (with the inequality reversed) applies to
                               an absolute minimum. Note that that absolute maximum or
                               minimum value is f (c). Its location is x = c.
                                   The existence of an absolute maximum and minimum
                               under certain conditions is guaranteed by the Extreme Value
                               Theorem:



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