Exercise 1.  This exercise relates to Figure 7.1.  

                    [Graphics:Images/UniformConvergenceModHome_gr_1.gif]          [Graphics:Images/UniformConvergenceModHome_gr_2.gif]

                                      Figure 7.1  The geometric series does not converge uniformly on  [Graphics:Images/UniformConvergenceModHome_gr_3.gif].  

 

1 (c).  Assuming that the graph is accurate to scale, what is the value of  n  in  [Graphics:Images/UniformConvergenceModHome_gr_46.gif]?  Explain.

Solution 1 (c).

See text and/or instructor's solution manual.

Solution.   From the graph, we approximate  [Graphics:../Images/UniformConvergenceModHome_gr_47.gif].   Using   [Graphics:../Images/UniformConvergenceModHome_gr_48.gif],  

we observe that   [Graphics:../Images/UniformConvergenceModHome_gr_49.gif]   and deduce that  [Graphics:../Images/UniformConvergenceModHome_gr_50.gif].  

                    [Graphics:../Images/UniformConvergenceModHome_gr_51.gif]          [Graphics:../Images/UniformConvergenceModHome_gr_52.gif]

                    The graphs of    [Graphics:../Images/UniformConvergenceModHome_gr_53.gif]   and   [Graphics:../Images/UniformConvergenceModHome_gr_54.gif].
                    It is revealed that   [Graphics:../Images/UniformConvergenceModHome_gr_55.gif].

We are done.   

Aside.  The partial sum  [Graphics:../Images/UniformConvergenceModHome_gr_56.gif]  looks close  [Graphics:../Images/UniformConvergenceModHome_gr_57.gif] over the interval  [Graphics:../Images/UniformConvergenceModHome_gr_58.gif].

Let us look at the image of the disk  [Graphics:../Images/UniformConvergenceModHome_gr_59.gif]  under the mappings  [Graphics:../Images/UniformConvergenceModHome_gr_60.gif],  for  [Graphics:../Images/UniformConvergenceModHome_gr_61.gif].  

                    [Graphics:../Images/UniformConvergenceModHome_gr_62.gif]          [Graphics:../Images/UniformConvergenceModHome_gr_63.gif]

  

                    [Graphics:../Images/UniformConvergenceModHome_gr_64.gif]          [Graphics:../Images/UniformConvergenceModHome_gr_65.gif]

                    The images of the disk  [Graphics:../Images/UniformConvergenceModHome_gr_66.gif] under  [Graphics:../Images/UniformConvergenceModHome_gr_67.gif],  for  [Graphics:../Images/UniformConvergenceModHome_gr_68.gif].  

                    [Graphics:../Images/UniformConvergenceModHome_gr_69.gif]          [Graphics:../Images/UniformConvergenceModHome_gr_70.gif]

                    The image of the disk  [Graphics:../Images/UniformConvergenceModHome_gr_71.gif] under the mapping  [Graphics:../Images/UniformConvergenceModHome_gr_72.gif].   

Aside.  In Section 10.2 we will learn that the image of the disk  [Graphics:../Images/UniformConvergenceModHome_gr_73.gif]  is the disk  [Graphics:../Images/UniformConvergenceModHome_gr_74.gif].

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

This solution is complements of the authors.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

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