Transcription of Residues and Contour Integration Problems
{{id}} {{{paragraph}}}
Residues and Contour Integration ProblemsClassify the singularity off(z)at the indicated (z) = cot(z) atz= 0. Ans. Simple The test for a simple pole atz= 0 is that limz 0zcot(z)exists and is not 0. We can use L H opital s rule:limz 0zcot(z) = limz 0zcos(z)sin(z)= limz 0cos(z) zsin(z)cos(z)= the singularity is a simple (z) =1+cos(z)(z )2atz= . Ans. Power series is the simplest way to do this. We can expandcos(z) in a Taylor series aboutz= . To do so, use the trig identitycos(z) = cos(z ). Next, expand 1 cos(z ) in a power seriesinz :1 + cos(z) = 1 cos(z ) =12!(z )2 14!(z )4+ From this, we get1 + cos(z)(z )2=(z )2(12 14!(z )2+ )(z )2=12 14!(z )2+ ,which is the Laurent series for1+cos(z)(z )2.
Residues and Contour Integration Problems Classify the singularity of f(z) at the indicated point. 1. f(z) = cot(z) at z= 0. Ans. Simple pole. Solution.
Domain:
Source:
Link to this page:
Please notify us if you found a problem with this document:
{{id}} {{{paragraph}}}
Table of Basic Integrals Basic Forms, Integrals, Brief Look at Gaussian Integrals, CCHHAAPTTEERR 1133, Definite Integrals, CCHHAAPTTEERR 1133 Definite Integrals, GAUSSIAN INTEGRALS, Gaussian, Some Handy Integrals, Colby College, Colby College Some Handy Integrals, Lamar University, Derivatives and Integrals, INTEGRAL CALCULUS - EXERCISES