## Finding indefinite integrals

I'm trying to find the following indefinite integrals, but seems they're hard to be simplified into common integrals.
Appreciate if anyone could provide some guidelines!

Q1: $
\int x {\arcsin {\frac {2e} {x}}} {\arccos {\frac {x}{2r}}} dx
$

Q2: $
\int \sqrt{1-\frac{4e^2}{x^2}} \arccos {\frac {x}{2r}} dx
$

Q3: $
\int {x^2} {\sqrt{4r^2-x^2}} \arcsin{\frac{2e}{x}} dx
$

Q4: $
\int {\sqrt{x^2-4e^2}}{\sqrt{4r^2-x^2}} dx
$