/ / 2 \ \
| | 36*x | |
| 9*|-1 + ---------|*atan(7*x) |
| | 2| |
| 343*x \ -2 + 9*x / 126*x |
2*|------------ - ---------------------------- + -----------------------|
| 2 2 / 2\ / 2\|
|/ 2\ -2 + 9*x \1 + 49*x /*\-2 + 9*x /|
\\1 + 49*x / /
-------------------------------------------------------------------------
2
-2 + 9*x
$$\frac{2 \left(\frac{343 x}{\left(49 x^{2} + 1\right)^{2}} + \frac{126 x}{\left(9 x^{2} - 2\right) \left(49 x^{2} + 1\right)} - \frac{9 \left(\frac{36 x^{2}}{9 x^{2} - 2} - 1\right) \operatorname{atan}{\left(7 x \right)}}{9 x^{2} - 2}\right)}{9 x^{2} - 2}$$
/ / 2 \ / 2 \ / 2 \ \
| | 196*x | | 36*x | | 18*x | |
| 343*|-1 + ---------| 189*|-1 + ---------| 972*x*|-1 + ---------|*atan(7*x)|
| | 2| 2 | 2| | 2| |
| \ 1 + 49*x / 18522*x \ -2 + 9*x / \ -2 + 9*x / |
2*|- -------------------- - ------------------------ - ----------------------- + --------------------------------|
| 2 2 / 2\ / 2\ 2 |
| / 2\ / 2\ / 2\ \1 + 49*x /*\-2 + 9*x / / 2\ |
\ \1 + 49*x / \1 + 49*x / *\-2 + 9*x / \-2 + 9*x / /
------------------------------------------------------------------------------------------------------------------
2
-2 + 9*x
$$\frac{2 \left(- \frac{18522 x^{2}}{\left(9 x^{2} - 2\right) \left(49 x^{2} + 1\right)^{2}} + \frac{972 x \left(\frac{18 x^{2}}{9 x^{2} - 2} - 1\right) \operatorname{atan}{\left(7 x \right)}}{\left(9 x^{2} - 2\right)^{2}} - \frac{343 \left(\frac{196 x^{2}}{49 x^{2} + 1} - 1\right)}{\left(49 x^{2} + 1\right)^{2}} - \frac{189 \left(\frac{36 x^{2}}{9 x^{2} - 2} - 1\right)}{\left(9 x^{2} - 2\right) \left(49 x^{2} + 1\right)}\right)}{9 x^{2} - 2}$$