Exercise 5.  Show that, for all z,  

5 (a).   [Graphics:Images/ComplexFunTrigModHome_gr_101.gif].  

Solution 5 (a).

See text and/or instructor's solution manual.

Solution.  This follows immediately from the identity   [Graphics:../Images/ComplexFunTrigModHome_gr_102.gif].  

                    [Graphics:../Images/ComplexFunTrigModHome_gr_103.gif]   

Aside.  We can let Mathematica double check our work.

[Graphics:../Images/ComplexFunTrigModHome_gr_104.gif]

[Graphics:../Images/ComplexFunTrigModHome_gr_105.gif]


[Graphics:../Images/ComplexFunTrigModHome_gr_106.gif]

[Graphics:../Images/ComplexFunTrigModHome_gr_107.gif]


[Graphics:../Images/ComplexFunTrigModHome_gr_108.gif]

[Graphics:../Images/ComplexFunTrigModHome_gr_109.gif]

Alternate Solution.   Use the Identity (5-34) [Graphics:../Images/ComplexFunTrigModHome_gr_110.gif]  and get:  

                    [Graphics:../Images/ComplexFunTrigModHome_gr_111.gif]  

We are done.   

Aside.  We can let Mathematica graph the compositions that are involved.

                    [Graphics:../Images/ComplexFunTrigModHome_gr_112.gif]          [Graphics:../Images/ComplexFunTrigModHome_gr_113.gif]

                    [Graphics:../Images/ComplexFunTrigModHome_gr_114.gif]          [Graphics:../Images/ComplexFunTrigModHome_gr_115.gif]

                    The composite mappings  [Graphics:../Images/ComplexFunTrigModHome_gr_116.gif],  [Graphics:../Images/ComplexFunTrigModHome_gr_117.gif],  [Graphics:../Images/ComplexFunTrigModHome_gr_118.gif],   

                    where  [Graphics:../Images/ComplexFunTrigModHome_gr_119.gif]  and  [Graphics:../Images/ComplexFunTrigModHome_gr_120.gif].   

                    [Graphics:../Images/ComplexFunTrigModHome_gr_121.gif]          [Graphics:../Images/ComplexFunTrigModHome_gr_122.gif]

                    The equivalent mapping   [Graphics:../Images/ComplexFunTrigModHome_gr_123.gif].    






                    [Graphics:../Images/ComplexFunTrigModHome_gr_124.gif]          [Graphics:../Images/ComplexFunTrigModHome_gr_125.gif]

                    [Graphics:../Images/ComplexFunTrigModHome_gr_126.gif]          [Graphics:../Images/ComplexFunTrigModHome_gr_127.gif]

                    The composite mappings  [Graphics:../Images/ComplexFunTrigModHome_gr_128.gif],  [Graphics:../Images/ComplexFunTrigModHome_gr_129.gif],  [Graphics:../Images/ComplexFunTrigModHome_gr_130.gif],   

                    where  [Graphics:../Images/ComplexFunTrigModHome_gr_131.gif]  and  [Graphics:../Images/ComplexFunTrigModHome_gr_132.gif].   

                    [Graphics:../Images/ComplexFunTrigModHome_gr_133.gif]          [Graphics:../Images/ComplexFunTrigModHome_gr_134.gif]

                    The equivalent mapping   [Graphics:../Images/ComplexFunTrigModHome_gr_135.gif].    

















 

This solution is complements of the authors.



































 

(c) 2008 John H. Mathews, Russell W. Howell