Problems with integration contours and residues

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SUMMARY

The discussion centers on the challenges of evaluating specific integrals involving exponential functions and residues. The first integral, Int[-inf;+inf;exp(-x^2)/(z-x)], yields a result of 2i pi exp(-z^2), while the second integral, Int[-inf;0;exp(x)/(z-x)] with z<0, results in 2i pi exp(-z) plus an additional term. These integrals are complex and cannot be solved straightforwardly using residue theory, as they lead to the error function and the incomplete gamma function.

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nullus 1er
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1. Hi there,

I have problems in finding the correct results for these integrals. I have to say I m not a great expert in residues...


2. Int[-inf;+inf;exp(-x^2)/(z-x)]

variable is x, constant is z

Int[-inf;0;exp(x)/(z-x)] with z<0


3. I think the 1st one gives 2i pi exp(-z^2) and the second one 2i pi exp(-z)+something
 
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These are not simple integrals that can be done by residues. The yields an error function and the second an incomplete gamma function.
 

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