$$9 x \left|{x}\right| + 5 + \frac{8}{x^{5}}$$
40
- -- + 9*|x| + 9*x*sign(x)
6
x
$$9 x \operatorname{sign}{\left(x \right)} + 9 \left|{x}\right| - \frac{40}{x^{6}}$$
/ 40 \
6*|3*sign(x) + -- + 3*x*DiracDelta(x)|
| 7 |
\ x /
$$6 \left(3 x \delta\left(x\right) + 3 \operatorname{sign}{\left(x \right)} + \frac{40}{x^{7}}\right)$$