$\begin{array}{l}\phantom{\phantom{;}x\phantom{;}+5;}{\phantom{;}x^{3}-5x^{2}+21x\phantom{;}-105\phantom{;}\phantom{;}}\\\phantom{;}x\phantom{;}+5\overline{\smash{)}\phantom{;}x^{4}\phantom{-;x^n}-4x^{2}\phantom{-;x^n}-2\phantom{;}\phantom{;}}\\\phantom{\phantom{;}x\phantom{;}+5;}\underline{-x^{4}-5x^{3}\phantom{-;x^n}\phantom{-;x^n}\phantom{-;x^n}}\\\phantom{-x^{4}-5x^{3};}-5x^{3}-4x^{2}\phantom{-;x^n}-2\phantom{;}\phantom{;}\\\phantom{\phantom{;}x\phantom{;}+5-;x^n;}\underline{\phantom{;}5x^{3}+25x^{2}\phantom{-;x^n}\phantom{-;x^n}}\\\phantom{;\phantom{;}5x^{3}+25x^{2}-;x^n;}\phantom{;}21x^{2}\phantom{-;x^n}-2\phantom{;}\phantom{;}\\\phantom{\phantom{;}x\phantom{;}+5-;x^n-;x^n;}\underline{-21x^{2}-105x\phantom{;}\phantom{-;x^n}}\\\phantom{;;-21x^{2}-105x\phantom{;}-;x^n-;x^n;}-105x\phantom{;}-2\phantom{;}\phantom{;}\\\phantom{\phantom{;}x\phantom{;}+5-;x^n-;x^n-;x^n;}\underline{\phantom{;}105x\phantom{;}+525\phantom{;}\phantom{;}}\\\phantom{;;;\phantom{;}105x\phantom{;}+525\phantom{;}\phantom{;}-;x^n-;x^n-;x^n;}\phantom{;}523\phantom{;}\phantom{;}\\\end{array}$

$x^{3}-5x^{2}+21x-105+\frac{523}{x+5}$