Example
4.14. Evaluate
.
Explore Solution 4.14.
We can use the definition of convergence of a series and find the limit of the partial sums.
![[Graphics:../Images/ComplexGeometricSeriesMod_gr_156.gif]](../Images/ComplexGeometricSeriesMod_gr_156.gif)
Or we can see that this is an infinite geometric series with
ratio
.
![[Graphics:../Images/ComplexGeometricSeriesMod_gr_159.gif]](../Images/ComplexGeometricSeriesMod_gr_159.gif)
The sum of the infinite geometric series is now found.
![[Graphics:../Images/ComplexGeometricSeriesMod_gr_161.gif]](../Images/ComplexGeometricSeriesMod_gr_161.gif)
Use Mathematica to construct some of the partial sums of the infinite series.
![[Graphics:../Images/ComplexGeometricSeriesMod_gr_163.gif]](../Images/ComplexGeometricSeriesMod_gr_163.gif)
Use Mathematica to plot some of the partial sums of the infinite series.
![[Graphics:../Images/ComplexGeometricSeriesMod_gr_165.gif]](../Images/ComplexGeometricSeriesMod_gr_165.gif)
![[Graphics:../Images/ComplexGeometricSeriesMod_gr_166.gif]](../Images/ComplexGeometricSeriesMod_gr_166.gif)
We see that the sum of the infinite geometric
series
.