$$\frac{e^{x}}{e^{2 x} + 1}$$
/ 2*x \
| 2*e | x
|1 - --------|*e
| 2*x|
\ 1 + e /
-----------------
2*x
1 + e
$$\frac{e^{x}}{e^{2 x} + 1} \left(1 - \frac{2 e^{2 x}}{e^{2 x} + 1}\right)$$
/ 2*x 4*x \
| 8*e 8*e | x
|1 - -------- + -----------|*e
| 2*x 2|
| 1 + e / 2*x\ |
\ \1 + e / /
-------------------------------
2*x
1 + e
$$\frac{e^{x}}{e^{2 x} + 1} \left(1 - \frac{8 e^{2 x}}{e^{2 x} + 1} + \frac{8 e^{4 x}}{\left(e^{2 x} + 1\right)^{2}}\right)$$