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

7 (a).  [Graphics:Images/ComplexFunPowerRootModHome_gr_513.gif].

Solution 7 (a).

See text and/or instructor's solution manual.

Answer.  [Graphics:../Images/ComplexFunPowerRootModHome_gr_514.gif].  

Solution.  Use polar coordinates  [Graphics:../Images/ComplexFunPowerRootModHome_gr_515.gif]  in the z-plane and  [Graphics:../Images/ComplexFunPowerRootModHome_gr_516.gif]  in the  w-plane.  The mapping  [Graphics:../Images/ComplexFunPowerRootModHome_gr_517.gif]  can be written as  

        [Graphics:../Images/ComplexFunPowerRootModHome_gr_518.gif],  
        
the point  [Graphics:../Images/ComplexFunPowerRootModHome_gr_519.gif]  in the xy-plane is mapped to the point  [Graphics:../Images/ComplexFunPowerRootModHome_gr_520.gif]  in the uv-plane,

and we get the equations    [Graphics:../Images/ComplexFunPowerRootModHome_gr_521.gif]  and  [Graphics:../Images/ComplexFunPowerRootModHome_gr_522.gif].  

The image of  set  [Graphics:../Images/ComplexFunPowerRootModHome_gr_523.gif]  under the the mapping  [Graphics:../Images/ComplexFunPowerRootModHome_gr_524.gif]  satisfies

        [Graphics:../Images/ComplexFunPowerRootModHome_gr_525.gif],  and  
        
        [Graphics:../Images/ComplexFunPowerRootModHome_gr_526.gif]  or  [Graphics:../Images/ComplexFunPowerRootModHome_gr_527.gif].  

Hence, the image set is  [Graphics:../Images/ComplexFunPowerRootModHome_gr_528.gif].

We are done.   

Aside.  We can let Mathematica double check our work.

                    

                    [Graphics:../Images/ComplexFunPowerRootModHome_gr_529.gif]         [Graphics:../Images/ComplexFunPowerRootModHome_gr_530.gif]

                    The image of the portion [Graphics:../Images/ComplexFunPowerRootModHome_gr_531.gif]under  [Graphics:../Images/ComplexFunPowerRootModHome_gr_532.gif]  is  [Graphics:../Images/ComplexFunPowerRootModHome_gr_533.gif].

 















 

This solution is complements of the authors.

 































 

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