1549312215-Complex_Analysis_for_Mathematics_and_Engineering_5th_edition__Mathews

7.3 • LAURENT $ERIES REPRESENTATIONS 271

What happens to the Laurent series if f is analytic in the disk Dn (a)? Look-

ing at Equation (7-29), we see that the coefficient for the positive power (zo - at

equals '1i! 1C~l(<o) by using Cauchy's integral formula f or derivatives. Hence the