$\begin{array}{l}\phantom{\phantom{;}x^{2}-8;}{\phantom{;}x\phantom{;}-1\phantom{;}\phantom{;}}\\\phantom{;}x^{2}-8\overline{\smash{)}\phantom{;}x^{3}-x^{2}+2x\phantom{;}+10\phantom{;}\phantom{;}}\\\phantom{\phantom{;}x^{2}-8;}\underline{-x^{3}\phantom{-;x^n}+8x\phantom{;}\phantom{-;x^n}}\\\phantom{-x^{3}+8x\phantom{;};}-x^{2}+10x\phantom{;}+10\phantom{;}\phantom{;}\\\phantom{\phantom{;}x^{2}-8-;x^n;}\underline{\phantom{;}x^{2}\phantom{-;x^n}-8\phantom{;}\phantom{;}}\\\phantom{;\phantom{;}x^{2}-8\phantom{;}\phantom{;}-;x^n;}\phantom{;}10x\phantom{;}+2\phantom{;}\phantom{;}\\\end{array}$

$x-1+\frac{10x+2}{x^2-8}$