Did I get these complex integrals right?(Complex Analysis)

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Raziel2701
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Homework Statement


Determine all possible values of the integral [tex]\int_{\gamma}\frac{z^2 +1}{z(z-1)}dz[/tex] where [tex]\gamma[/tex] is an oriented circle in C\{0,1}.


Homework Equations





The Attempt at a Solution


I dismantled the integrand by using partial fraction decomposition after doing some long division and so I get the equivalent integral:

[tex]\int_\gamma dz +\int_\gamma \frac{2}{z-1}dz -\int_\gamma \frac{1}{z}dz[/tex]

So I evaluated that integral over the next four contours.
Gamma 1, circle radius 1/2 centered at 1.
Gamma 2, circle centered at origin, radius 1/2.
Gamma 3, circle that did not encircle neither of the singularities.
Gamma 4, circle centered at origin radius 2.

For each contour respectively I got the following results:
G1:4pi(i)
G2:-2pi(i)
G3:0
G4:2pi(i)

Are these correct?
 
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Hi Raziel2701! :smile:

(have a pi: π and a gamma: γ :wink:)
Raziel2701 said:
For each contour respectively I got the following results:
G1:4pi(i)
G2:-2pi(i)
G3:0
G4:2pi(i)

Are these correct?

Looks good! :smile:

except, what if γ is the other way round? :wink:
 
If gamma ran counterclockwise, then answers would differ by a negative factor no?
 
(a negative factor? you mean -1 !)

yes :smile: