\(=\lim\left(\sqrt[3]{n^3+3n^2+1}-\left(n+1\right)+\left(n+1\right)-\sqrt{n^2+2n}\right)\)
\(=\lim\left(\frac{-3n}{\sqrt[3]{\left(n^3+3n^2+1\right)^2}+\left(n+1\right)\sqrt[3]{n^3+3n^2+1}+\left(n+1\right)^2}+\frac{1}{n+1+\sqrt{n^2+2n}}\right)\)
\(=0+0=0\)