2*x
2*atan(x) + ------
2
1 + x
$$\frac{2 x}{x^{2} + 1} + 2 \operatorname{atan}{\left (x \right )}$$
/ 2 \
| x |
4*|1 - ------|
| 2|
\ 1 + x /
--------------
2
1 + x
$$\frac{1}{x^{2} + 1} \left(- \frac{4 x^{2}}{x^{2} + 1} + 4\right)$$
/ 2 \
| x |
16*x*|-1 + ------|
| 2|
\ 1 + x /
------------------
2
/ 2\
\1 + x /
$$\frac{16 x}{\left(x^{2} + 1\right)^{2}} \left(\frac{x^{2}}{x^{2} + 1} - 1\right)$$