The third derivative
[src]
/ / 2 \ \
| | 4*x | |
| 2*|-1 + ------|*sin(x)|
| | 2| |
| 3*sin(x) 6*x*cos(x) \ 1 + x / |
5*|-atan(x)*cos(x) - -------- - ---------- + ----------------------|
| 2 2 2 |
| 1 + x / 2\ / 2\ |
\ \1 + x / \1 + x / /
$$5 \left(- \frac{6 x \cos{\left(x \right)}}{\left(x^{2} + 1\right)^{2}} - \cos{\left(x \right)} \operatorname{atan}{\left(x \right)} - \frac{3 \sin{\left(x \right)}}{x^{2} + 1} + \frac{2 \left(\frac{4 x^{2}}{x^{2} + 1} - 1\right) \sin{\left(x \right)}}{\left(x^{2} + 1\right)^{2}}\right)$$