Example
8.16. Evaluate
.
![[Graphics:Images/IntegralsRationalMod_gr_87.gif]](../Images/IntegralsRationalMod_gr_87.gif)
Explore Solution 8.16.
Enter the function
and
locate the singularities.
![[Graphics:../Images/IntegralsRationalMod_gr_96.gif]](../Images/IntegralsRationalMod_gr_96.gif)
Which poles lie in the upper half plane ?
![[Graphics:../Images/IntegralsRationalMod_gr_98.gif]](../Images/IntegralsRationalMod_gr_98.gif)
![[Graphics:../Images/IntegralsRationalMod_gr_99.gif]](../Images/IntegralsRationalMod_gr_99.gif)
Compute the residues at
,
and use the residue calculus to compute the value of the
integral.
![]()
![[Graphics:../Images/IntegralsRationalMod_gr_103.gif]](../Images/IntegralsRationalMod_gr_103.gif)
![[Graphics:../Images/IntegralsRationalMod_gr_104.gif]](../Images/IntegralsRationalMod_gr_104.gif)
Or, we can use Mathematica's integral table and evaluate the integral.
![]()
However, for this simple integral Mathematica's can find the correct answer without resorting to the PrincipalValue option.
![[Graphics:../Images/IntegralsRationalMod_gr_108.gif]](../Images/IntegralsRationalMod_gr_108.gif)
The above answer is correct too.