Problems with integration contours and residues

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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.
 
Prove $$\int\limits_0^{\sqrt2/4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx = \frac{\pi^2}{8}.$$ Let $$I = \int\limits_0^{\sqrt 2 / 4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx. \tag{1}$$ The representation integral of ##\arcsin## is $$\arcsin u = \int\limits_{0}^{1} \frac{\mathrm dt}{\sqrt{1-t^2}}, \qquad 0 \leqslant u \leqslant 1.$$ Plugging identity above into ##(1)## with ##u...
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