Example 27.  The conformal mapping  [Graphics:Images/ConformalMapDictionary.3.1_gr_43.gif].
It can be constructed via the Schwarz-Christoffel integral  [Graphics:Images/ConformalMapDictionary.3.1_gr_44.gif],  
also  [Graphics:Images/ConformalMapDictionary.3.1_gr_45.gif].  
The image of the upper half-plane  [Graphics:Images/ConformalMapDictionary.3.1_gr_46.gif]  is the semi-infinite strip  [Graphics:Images/ConformalMapDictionary.3.1_gr_47.gif], and the angles are [Graphics:Images/ConformalMapDictionary.3.1_gr_48.gif].
Remark. Hint: Set  [Graphics:Images/ConformalMapDictionary.3.1_gr_49.gif]  and  [Graphics:Images/ConformalMapDictionary.3.1_gr_50.gif], and the angles are [Graphics:Images/ConformalMapDictionary.3.1_gr_51.gif].

 [Graphics:Images/ConformalMapDictionary.3.1_gr_52.gif]    [Graphics:Images/ConformalMapDictionary.3.1_gr_53.gif]

 

Consider the result that we saw in Example 25 and the conformal mapping    [Graphics:../Images/ConformalMapDictionary.3.1_gr_54.gif]
The image of the upper half-plane  [Graphics:../Images/ConformalMapDictionary.3.1_gr_55.gif]  is the portion of the upper half-plane  [Graphics:../Images/ConformalMapDictionary.3.1_gr_56.gif]  that lies outside the unit circle  [Graphics:../Images/ConformalMapDictionary.3.1_gr_57.gif].  

 

[Graphics:../Images/ConformalMapDictionary.3.1_gr_58.gif]    [Graphics:../Images/ConformalMapDictionary.3.1_gr_59.gif]

Notice that the conformal mapping  [Graphics:../Images/ConformalMapDictionary.3.1_gr_60.gif] is similar and will also map the upper half-plane  [Graphics:../Images/ConformalMapDictionary.3.1_gr_61.gif]  onto the portion of the upper half-plane  [Graphics:../Images/ConformalMapDictionary.3.1_gr_62.gif]  that lies outside the unit circle  [Graphics:../Images/ConformalMapDictionary.3.1_gr_63.gif].  

 

[Graphics:../Images/ConformalMapDictionary.3.1_gr_64.gif]    [Graphics:../Images/ConformalMapDictionary.3.1_gr_65.gif]

Use familiar properties of the logarithm [Graphics:../Images/ConformalMapDictionary.3.1_gr_66.gif], which maps the upper half-plane  [Graphics:../Images/ConformalMapDictionary.3.1_gr_67.gif]  onto the infinite strip  [Graphics:../Images/ConformalMapDictionary.3.1_gr_68.gif].

 

[Graphics:../Images/ConformalMapDictionary.3.1_gr_69.gif]    [Graphics:../Images/ConformalMapDictionary.3.1_gr_70.gif]

Therefore, the desired conformal mapping is the composition mapping  [Graphics:../Images/ConformalMapDictionary.3.1_gr_71.gif],
the image of the upper half-plane  [Graphics:../Images/ConformalMapDictionary.3.1_gr_72.gif]   is the semi-infinite strip  [Graphics:../Images/ConformalMapDictionary.3.1_gr_73.gif].

 

[Graphics:../Images/ConformalMapDictionary.3.1_gr_74.gif]    [Graphics:../Images/ConformalMapDictionary.3.1_gr_75.gif]

                                                         The conformal mapping  [Graphics:Images/ConformalMapDictionary.3.1_gr_43.gif].

[Graphics:../Images/ConformalMapDictionary.3.1_gr_76.gif]    [Graphics:../Images/ConformalMapDictionary.3.1_gr_77.gif]

 

[Graphics:../Images/ConformalMapDictionary.3.1_gr_78.gif]                           [Graphics:../Images/ConformalMapDictionary.3.1_gr_79.gif]

 

Details 27.

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