Page 130 - Essentials of applied mathematics for scientists and engineers
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book   Mobk070    March 22, 2007  11:7








                     120  ESSENTIALS OF APPLIED MATHEMATICS FOR SCIENTISTS AND ENGINEERS
                            We can formally differentiate the above equation n times with respect to z 0 and find an
                       extension as
                                                            n!        f (z)
                                                  f  (n) (z 0 ) =            dz                     (7.29)
                                                           2πi   C  (z − z 0 ) n+1
                       Problems
                          1. Show that
                              (a) sinh z = sinh x cos y + i cosh x sin y
                              (b) cos z = cos x cosh y − i sin x sinh y

                              and show that each is entire.
                          2. Find all of the values of
                                        √   3
                              (a) (−1 + i 3) 2
                                   1
                              (b) 8 6
                          3. Find all the roots of the equation

                              sin z = cosh 4
                          4. Find all the zeros of
                              (a) sinh z
                              (b) cosh z
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