2
2 2*x
------ - ---------
2 2
1 + x / 2\
\1 + x /
$$- \frac{2 x^{2}}{\left(x^{2} + 1\right)^{2}} + \frac{2}{x^{2} + 1}$$
/ 2 \
| x |
8*x*|-1 + ------|
| 2|
\ 1 + x /
-----------------
2
/ 2\
\1 + x /
$$\frac{8 x \left(\frac{x^{2}}{x^{2} + 1} - 1\right)}{\left(x^{2} + 1\right)^{2}}$$
/ 4 2 \
| 6*x 7*x |
8*|-1 - --------- + ------|
| 2 2|
| / 2\ 1 + x |
\ \1 + x / /
---------------------------
2
/ 2\
\1 + x /
$$\frac{8 \left(- \frac{6 x^{4}}{\left(x^{2} + 1\right)^{2}} + \frac{7 x^{2}}{x^{2} + 1} - 1\right)}{\left(x^{2} + 1\right)^{2}}$$