$\begin{array}{l}\phantom{\phantom{;}x\phantom{;}+1;}{\phantom{;}4x^{2}-5x\phantom{;}+10\phantom{;}\phantom{;}}\\\phantom{;}x\phantom{;}+1\overline{\smash{)}\phantom{;}4x^{3}-x^{2}+5x\phantom{;}-10\phantom{;}\phantom{;}}\\\phantom{\phantom{;}x\phantom{;}+1;}\underline{-4x^{3}-4x^{2}\phantom{-;x^n}\phantom{-;x^n}}\\\phantom{-4x^{3}-4x^{2};}-5x^{2}+5x\phantom{;}-10\phantom{;}\phantom{;}\\\phantom{\phantom{;}x\phantom{;}+1-;x^n;}\underline{\phantom{;}5x^{2}+5x\phantom{;}\phantom{-;x^n}}\\\phantom{;\phantom{;}5x^{2}+5x\phantom{;}-;x^n;}\phantom{;}10x\phantom{;}-10\phantom{;}\phantom{;}\\\phantom{\phantom{;}x\phantom{;}+1-;x^n-;x^n;}\underline{-10x\phantom{;}-10\phantom{;}\phantom{;}}\\\phantom{;;-10x\phantom{;}-10\phantom{;}\phantom{;}-;x^n-;x^n;}-20\phantom{;}\phantom{;}\\\end{array}$

$4x^{2}-5x+10+\frac{-20}{x+1}$