#INtegration by part
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ı dont understand the last part
how u.arcsinu - ........
queal to
root(1-lnx) + ......
@quick spire
they do a substitution $t = 1-u^2$ so $dt = -2u du$ and the integral becomes
$$ \int \frac{u}{\sqrt{1-u^2}} du = -\frac{1}{2} \int \frac{1}{\sqrt{t}}dt$$
zlik
Dos this help?
for $\int \arcsin(u) du$ they use integration by parts. Firstly, they write the integral as $$\int 1\cdot \arcsin(u)du$$ Then they take the derivative of $\arcsin(u)$ which is $\frac{1}{\sqrt{1-u^2}}$ and the anti-derivative of $1$ which is $u$. Therefore
$$\int \arcsin(u) du$$ $$= \int 1\cdot \arcsin(u)du$$ $$= u\cdot \arcsin(u) - \int \frac{u}{\sqrt{1-u^2}} du$$
zlik