Example 4.3.  Show that the series  [Graphics:Images/ComplexSequenceSeriesMod_gr_140.gif]  [Graphics:Images/ComplexSequenceSeriesMod_gr_141.gif]is convergent.

Solution.  Recall that the real series  [Graphics:Images/ComplexSequenceSeriesMod_gr_142.gif]  and  [Graphics:Images/ComplexSequenceSeriesMod_gr_143.gif]  are convergent.  Hence, Theorem 4.4 implies that the given complex series is convergent.  

Explore Solution 4.3.

Enter the formula for the series, and determine if the series converges or diverges.

[Graphics:../Images/ComplexSequenceSeriesMod_gr_144.gif]

 

 

 

 

 

[Graphics:../Images/ComplexSequenceSeriesMod_gr_145.gif]

 

 

Use Mathematica to construct some of the partial sums of the infinite series.

[Graphics:../Images/ComplexSequenceSeriesMod_gr_146.gif]

 

 

 

 

 

[Graphics:../Images/ComplexSequenceSeriesMod_gr_147.gif]

 

 

Use Mathematica to compute some of the partial sums of the infinite series.

[Graphics:../Images/ComplexSequenceSeriesMod_gr_148.gif]




[Graphics:../Images/ComplexSequenceSeriesMod_gr_149.gif]

[Graphics:../Images/ComplexSequenceSeriesMod_gr_150.gif]

 

 

Use Mathematica to plot some of the partial sums of the infinite series.

[Graphics:../Images/ComplexSequenceSeriesMod_gr_151.gif]

 

 

 

 

 

 

[Graphics:../Images/ComplexSequenceSeriesMod_gr_152.gif]

[Graphics:../Images/ComplexSequenceSeriesMod_gr_153.gif]

Therefore, we see that the infinite series converges, indeed  [Graphics:../Images/ComplexSequenceSeriesMod_gr_154.gif].  

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

(c) 2006 John H. Mathews, Russell W. Howell