Complex Line Integral (not too hard)

Jamin2112
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Homework Statement



∫dz/(z4+1) integrated over the curve C1(1+i)

Homework Equations



The only thing we learned in this chapter is Cauchy's integral formula, so I'm assuming that comes in somehow.

The Attempt at a Solution



∫dz/(z4+1) = ∫dz/(z+1+i)(z+1-i)(z-1+i)(z-1-i)

Not bad, eh? Where do I go from here.
 
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Look for the poles of your integrand (for which values of z is the denominator 0).
Now find out which of them lie inside of the curve.
Now apply Cauchy's formula.
 
susskind_leon said:
Look for the poles of your integrand (for which values of z is the denominator 0).
Now find out which of them lie inside of the curve.
Now apply Cauchy's formula.

Ah, I see now!
 
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