\(=lim\frac{-2n+4}{\left(n+1\right)\left(\sqrt[3]{\left(n^3-2n+4\right)^2}+n\sqrt[3]{n^3-2n+4}+n^2\right)}\)
\(=lim\left(\frac{-2+\frac{4}{n}}{\left(1+\frac{1}{n}\right)\left(n+1\right)\left(\sqrt[3]{\left(n^3-2n+4\right)^2}+n\sqrt[3]{n^3-2n+4}+n^2\right)}\right)=\frac{-2}{\infty}=0\)