$$\frac{9}{81 x^{2} + 1}$$
-1458*x
------------
2
/ 2\
\1 + 81*x /
$$- \frac{1458 x}{\left(81 x^{2} + 1\right)^{2}}$$
/ 2 \
| 324*x |
1458*|-1 + ---------|
| 2|
\ 1 + 81*x /
---------------------
2
/ 2\
\1 + 81*x /
$$\frac{\frac{472392 x^{2}}{81 x^{2} + 1} - 1458}{\left(81 x^{2} + 1\right)^{2}}$$