Exercise 3.  Show that   [Graphics:Images/SchwarzChristoffelModHome_gr_78.gif]   maps the upper half-plane   [Graphics:Images/SchwarzChristoffelModHome_gr_79.gif]   

onto the domain indicated in Figure 11.77.                     Figure 11.77.

Hint.  Set   [Graphics:Images/SchwarzChristoffelModHome_gr_80.gif],  [Graphics:Images/SchwarzChristoffelModHome_gr_81.gif],   and   [Graphics:Images/SchwarzChristoffelModHome_gr_82.gif],  [Graphics:Images/SchwarzChristoffelModHome_gr_83.gif],   respectively.  

Solution 3.

See text and/or instructor's solution manual.

Answer.   [Graphics:../Images/SchwarzChristoffelModHome_gr_84.gif],   integrate and get   [Graphics:../Images/SchwarzChristoffelModHome_gr_85.gif],  

then use the conditions   [Graphics:../Images/SchwarzChristoffelModHome_gr_86.gif],   and obtain   [Graphics:../Images/SchwarzChristoffelModHome_gr_87.gif].

Solution.   Along the x-axis use the points   [Graphics:../Images/SchwarzChristoffelModHome_gr_88.gif].   The exterior angles are  [Graphics:../Images/SchwarzChristoffelModHome_gr_89.gif],  

and the formula for the derivative [Graphics:../Images/SchwarzChristoffelModHome_gr_90.gif] is  given by the Schwarz-Christoffel formula  

                    [Graphics:../Images/SchwarzChristoffelModHome_gr_91.gif]  

Integrate and get

                    [Graphics:../Images/SchwarzChristoffelModHome_gr_92.gif]   

The images of   [Graphics:../Images/SchwarzChristoffelModHome_gr_93.gif],   are   [Graphics:../Images/SchwarzChristoffelModHome_gr_94.gif],   respectively.

Use   [Graphics:../Images/SchwarzChristoffelModHome_gr_95.gif],   and obtain the system of equations

                    [Graphics:../Images/SchwarzChristoffelModHome_gr_96.gif]

Then get

                    [Graphics:../Images/SchwarzChristoffelModHome_gr_97.gif]

The values  [Graphics:../Images/SchwarzChristoffelModHome_gr_98.gif]  are solutions for this system of equations.

Therefore,   

                    [Graphics:../Images/SchwarzChristoffelModHome_gr_99.gif].

 

We are done.   

 

Aside.  We can let Mathematica double check our work.

[Graphics:../Images/SchwarzChristoffelModHome_gr_100.gif]

[Graphics:../Images/SchwarzChristoffelModHome_gr_101.gif]


[Graphics:../Images/SchwarzChristoffelModHome_gr_102.gif]

[Graphics:../Images/SchwarzChristoffelModHome_gr_103.gif]


[Graphics:../Images/SchwarzChristoffelModHome_gr_104.gif]

[Graphics:../Images/SchwarzChristoffelModHome_gr_105.gif]

Aside.  For illustration purposes we can graph the mapping   [Graphics:../Images/SchwarzChristoffelModHome_gr_106.gif].  



                    [Graphics:../Images/SchwarzChristoffelModHome_gr_108.gif]          [Graphics:../Images/SchwarzChristoffelModHome_gr_109.gif]

  

                    The image of the upper half plane  [Graphics:../Images/SchwarzChristoffelModHome_gr_110.gif]  under a conformal branch of

                    the mapping   [Graphics:../Images/SchwarzChristoffelModHome_gr_111.gif].  

 

We are really done.   

 

Or if you prefer, the logarithm term can be converted to an Arcsin term.

                    [Graphics:../Images/SchwarzChristoffelModHome_gr_112.gif].

Summary of Results.   The following two mapping of the upper half-plane will produce the same results.

[Graphics:../Images/SchwarzChristoffelModHome_gr_113.gif]



                    [Graphics:../Images/SchwarzChristoffelModHome_gr_115.gif]          [Graphics:../Images/SchwarzChristoffelModHome_gr_116.gif]

  

                    The image of the upper half plane  [Graphics:../Images/SchwarzChristoffelModHome_gr_117.gif]  under a conformal branch of  

                    the mapping   [Graphics:../Images/SchwarzChristoffelModHome_gr_118.gif].  

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

This solution is complements of the authors.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

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