Page 165 - Calculus Demystified
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CHAPTER 6
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                                                               Fig. 6.2 Transcendental Functions


                               discuss the function ln |x| when x  = 0 (Fig. 6.3):














                                                               Fig. 6.3
                                  If x  = 0 then

                                                          d           1
                                                            (ln |x|) =  .
                                                          dx          x
                               In other words,

                                                          1
                                                            dx = ln |x|+ C.
                                                          x
                                  More generally, we have

                                                          d         1 du
                                                            ln |u|=
                                                         dx         u dx
                               and

                                                        1 du
                                                             dx = ln |u|+ C.
                                                        u dx
                                   EXAMPLE 6.4
                                   Calculate

                                                       4               1
                                                          dx,               dx.
                                                     x + 1          −2 + 3x
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