∫ z 2 1 + z 3 3 d z {\displaystyle \int {\cfrac {z^{2}}{\sqrt[{3}]{1+z^{3}}}}dz}
u = 1 + z 3 d u = 3 z 2 d z 1 3 d u = z 2 d z {\displaystyle {\begin{aligned}u&=1+{z}^{3}\\[2ex]du&=3{z}^{2}dz\\[2ex]{\frac {1}{3}}du&={z}^{2}dz\\[2ex]\end{aligned}}}
∫ z 2 1 + z 3 3 d z = 1 3 ∫ 1 u 3 d u {\displaystyle {\begin{aligned}\int {\cfrac {z^{2}}{\sqrt[{3}]{1+z^{3}}}}dz&={\frac {1}{3}}\int {\frac {1}{\sqrt[{3}]{u}}}du\end{aligned}}}