-2*acot(x)
----------
2
1 + x
2*(1 + 2*x*acot(x))
-------------------
2
/ 2\
\1 + x /
/ 2 \
| 3*x 4*x *acot(x) |
4*|- ------ - ------------ + acot(x)|
| 2 2 |
\ 1 + x 1 + x /
-------------------------------------
2
/ 2\
\1 + x /