3
x 2
------ + 3*x *atan(x)
2
1 + x
$$3 x^{2} \operatorname{atan}{\left(x \right)} + \frac{x^{3}}{x^{2} + 1}$$
/ 3 \
| x 3*x |
2*x*|3*atan(x) - --------- + ------|
| 2 2|
| / 2\ 1 + x |
\ \1 + x / /
$$2 x \left(- \frac{x^{3}}{\left(x^{2} + 1\right)^{2}} + 3 \operatorname{atan}{\left(x \right)} + \frac{3 x}{x^{2} + 1}\right)$$
/ / 2 \\
| 3 | 4*x ||
| x *|-1 + ------||
| 3 | 2||
| 9*x 9*x \ 1 + x /|
2*|3*atan(x) - --------- + ------ + ----------------|
| 2 2 2 |
| / 2\ 1 + x / 2\ |
\ \1 + x / \1 + x / /
$$2 \left(\frac{x^{3} \cdot \left(\frac{4 x^{2}}{x^{2} + 1} - 1\right)}{\left(x^{2} + 1\right)^{2}} - \frac{9 x^{3}}{\left(x^{2} + 1\right)^{2}} + 3 \operatorname{atan}{\left(x \right)} + \frac{9 x}{x^{2} + 1}\right)$$