Exercise 1.  State where the following mappings are conformal.  

1. (d)   [Graphics:Images/ConformalMappingModHome_gr_101.gif].  

Solution 1 (d).

See text and/or instructor's solution manual.

Answer.   [Graphics:../Images/ConformalMappingModHome_gr_102.gif]  is conformal for all [Graphics:../Images/ConformalMappingModHome_gr_103.gif] except  [Graphics:../Images/ConformalMappingModHome_gr_104.gif].  

Solution.   Calculate [Graphics:../Images/ConformalMappingModHome_gr_105.gif] and determine where  [Graphics:../Images/ConformalMappingModHome_gr_106.gif].  

                    [Graphics:../Images/ConformalMappingModHome_gr_107.gif]   

Since   [Graphics:../Images/ConformalMappingModHome_gr_108.gif]  for all  [Graphics:../Images/ConformalMappingModHome_gr_109.gif],   [Graphics:../Images/ConformalMappingModHome_gr_110.gif]  only at the point  [Graphics:../Images/ConformalMappingModHome_gr_111.gif].  

Therefore, [Graphics:../Images/ConformalMappingModHome_gr_112.gif]  is conformal for all [Graphics:../Images/ConformalMappingModHome_gr_113.gif] except  [Graphics:../Images/ConformalMappingModHome_gr_114.gif].  

We are done.   

Aside.  We can let Mathematica double check our work.

[Graphics:../Images/ConformalMappingModHome_gr_115.gif]

[Graphics:../Images/ConformalMappingModHome_gr_116.gif]


[Graphics:../Images/ConformalMappingModHome_gr_117.gif]

[Graphics:../Images/ConformalMappingModHome_gr_118.gif]
[Graphics:../Images/ConformalMappingModHome_gr_119.gif]
[Graphics:../Images/ConformalMappingModHome_gr_120.gif]

We are really done.   

Aside.  We can let Mathematica illustrate our work.

                    [Graphics:../Images/ConformalMappingModHome_gr_121.gif]          [Graphics:../Images/ConformalMappingModHome_gr_122.gif]

                    A small portion of the mapping  [Graphics:../Images/ConformalMappingModHome_gr_123.gif].  

                    [Graphics:../Images/ConformalMappingModHome_gr_124.gif]          [Graphics:../Images/ConformalMappingModHome_gr_125.gif]

                    Another small portion of the mapping  [Graphics:../Images/ConformalMappingModHome_gr_126.gif].  

 

 

We are really really done.

Caveat.  At a point  [Graphics:../Images/ConformalMappingModHome_gr_127.gif]  where  [Graphics:../Images/ConformalMappingModHome_gr_128.gif]   we will have

                    [Graphics:../Images/ConformalMappingModHome_gr_129.gif].

Applying Theorem 10.2 we see that the mapping  [Graphics:../Images/ConformalMappingModHome_gr_130.gif] magnifies angles at the vertex  [Graphics:../Images/ConformalMappingModHome_gr_131.gif]  by the factor  [Graphics:../Images/ConformalMappingModHome_gr_132.gif].

                    [Graphics:../Images/ConformalMappingModHome_gr_133.gif]          [Graphics:../Images/ConformalMappingModHome_gr_134.gif]

                      For   [Graphics:../Images/ConformalMappingModHome_gr_135.gif]  at  [Graphics:../Images/ConformalMappingModHome_gr_136.gif]  we have   [Graphics:../Images/ConformalMappingModHome_gr_137.gif]   and   [Graphics:../Images/ConformalMappingModHome_gr_138.gif],  and
                      the mapping  [Graphics:../Images/ConformalMappingModHome_gr_139.gif] magnifies angles at the vertex  [Graphics:../Images/ConformalMappingModHome_gr_140.gif]  by the factor  [Graphics:../Images/ConformalMappingModHome_gr_141.gif].

 

Remark.  In Section 10.3 and Section 10.4 we will study some composite mappings involving  [Graphics:../Images/ConformalMappingModHome_gr_142.gif].

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

This solution is complements of the authors.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

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