$\int_0^\infty(\mathrm{erf}^2(cx)\exp(-x^2)x^2\,dx$,$c \in\mathbb{C}$

72 Views Asked by At

Does someone know useful formulae that might help evaluating this integral?

$$\int_0^\infty\mathrm{erf}^2(cx)\exp(-x^2)x^2\,dx,\quad c \in\mathbb{C}$$

1

There are 1 best solutions below

4
On

Your integral (let's call it $J(c)$) is $${\frac {\arctan \left( \sqrt {2\,{c}^{2}+1} \right) }{\sqrt {\pi}}}-\frac{\sqrt{\pi}} 4+{\frac {{c}^{2}}{\sqrt {\pi (2\,{c}^{2}+1)} \left( {c}^{2}+1 \right) }} $$

at least for real $c$, where the integral converges. Note that

$$ \dfrac{dJ}{dc} = {\frac {5\,{c}^{3}+3\,c}{\sqrt {\pi} \left( 2\,{c}^{2}+1 \right) ^{3/2 } \left( {c}^{2}+1 \right) ^{2}}} $$ and integrate...