-1
-----------------
2/3 / 2/3\
3*x *\1 + x /
$$- \frac{1}{3 x^{\frac{2}{3}} \left(x^{\frac{2}{3}} + 1\right)}$$
/ 1 1 \
2*|---- + ------------|
| 5/3 / 2/3\|
\x x*\1 + x //
-----------------------
/ 2/3\
9*\1 + x /
$$\frac{\frac{2}{x \left(x^{\frac{2}{3}} + 1\right)} + \frac{2}{x^{\frac{5}{3}}}}{9 x^{\frac{2}{3}} + 9}$$
/ 5 4 5 \
-2*|---- + ---------------- + -------------|
| 8/3 2 2 / 2/3\|
|x 4/3 / 2/3\ x *\1 + x /|
\ x *\1 + x / /
--------------------------------------------
/ 2/3\
27*\1 + x /
$$- \frac{1}{27 x^{\frac{2}{3}} + 27} \left(\frac{10}{x^{2} \left(x^{\frac{2}{3}} + 1\right)} + \frac{8}{x^{\frac{4}{3}} \left(x^{\frac{2}{3}} + 1\right)^{2}} + \frac{10}{x^{\frac{8}{3}}}\right)$$