Exercise 7.  Find the image of  [Graphics:Images/ComplexFunPowerRootModHome_gr_512.gif]  under the following mappings.  

7 (c).  [Graphics:Images/ComplexFunPowerRootModHome_gr_555.gif].

Solution 7 (c).

See text and/or instructor's solution manual.

Answer.  [Graphics:../Images/ComplexFunPowerRootModHome_gr_556.gif].  

Solution.  Use polar coordinates  [Graphics:../Images/ComplexFunPowerRootModHome_gr_557.gif]  in the z-plane and  [Graphics:../Images/ComplexFunPowerRootModHome_gr_558.gif]  in the  w-plane.  The mapping  [Graphics:../Images/ComplexFunPowerRootModHome_gr_559.gif]  can be written as  

        [Graphics:../Images/ComplexFunPowerRootModHome_gr_560.gif],  
        
the point  [Graphics:../Images/ComplexFunPowerRootModHome_gr_561.gif]  in the xy-plane is mapped to the point  [Graphics:../Images/ComplexFunPowerRootModHome_gr_562.gif]  in the uv-plane,

and we get the equations    [Graphics:../Images/ComplexFunPowerRootModHome_gr_563.gif]  and  [Graphics:../Images/ComplexFunPowerRootModHome_gr_564.gif].      

The image of  set  [Graphics:../Images/ComplexFunPowerRootModHome_gr_565.gif]  under the the mapping  [Graphics:../Images/ComplexFunPowerRootModHome_gr_566.gif]  satisfies

        [Graphics:../Images/ComplexFunPowerRootModHome_gr_567.gif],  and  
        
        [Graphics:../Images/ComplexFunPowerRootModHome_gr_568.gif]  or  [Graphics:../Images/ComplexFunPowerRootModHome_gr_569.gif].  

Hence, the image set is  [Graphics:../Images/ComplexFunPowerRootModHome_gr_570.gif].

We are done.   

Aside.  We can let Mathematica double check our work.

                    

                    [Graphics:../Images/ComplexFunPowerRootModHome_gr_571.gif]         [Graphics:../Images/ComplexFunPowerRootModHome_gr_572.gif]

  

          The image of the portion [Graphics:../Images/ComplexFunPowerRootModHome_gr_573.gif]under  [Graphics:../Images/ComplexFunPowerRootModHome_gr_574.gif]  is  [Graphics:../Images/ComplexFunPowerRootModHome_gr_575.gif].

 















 

This solution is complements of the authors.

 































 

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