$\begin{array}{l}\phantom{\phantom{;}x\phantom{;}-2;}{\phantom{;}x^{3}-6x^{2}-12x\phantom{;}-21\phantom{;}\phantom{;}}\\\phantom{;}x\phantom{;}-2\overline{\smash{)}\phantom{;}x^{4}-8x^{3}\phantom{-;x^n}+3x\phantom{;}+10\phantom{;}\phantom{;}}\\\phantom{\phantom{;}x\phantom{;}-2;}\underline{-x^{4}+2x^{3}\phantom{-;x^n}\phantom{-;x^n}\phantom{-;x^n}}\\\phantom{-x^{4}+2x^{3};}-6x^{3}\phantom{-;x^n}+3x\phantom{;}+10\phantom{;}\phantom{;}\\\phantom{\phantom{;}x\phantom{;}-2-;x^n;}\underline{\phantom{;}6x^{3}-12x^{2}\phantom{-;x^n}\phantom{-;x^n}}\\\phantom{;\phantom{;}6x^{3}-12x^{2}-;x^n;}-12x^{2}+3x\phantom{;}+10\phantom{;}\phantom{;}\\\phantom{\phantom{;}x\phantom{;}-2-;x^n-;x^n;}\underline{\phantom{;}12x^{2}-24x\phantom{;}\phantom{-;x^n}}\\\phantom{;;\phantom{;}12x^{2}-24x\phantom{;}-;x^n-;x^n;}-21x\phantom{;}+10\phantom{;}\phantom{;}\\\phantom{\phantom{;}x\phantom{;}-2-;x^n-;x^n-;x^n;}\underline{\phantom{;}21x\phantom{;}-42\phantom{;}\phantom{;}}\\\phantom{;;;\phantom{;}21x\phantom{;}-42\phantom{;}\phantom{;}-;x^n-;x^n-;x^n;}-32\phantom{;}\phantom{;}\\\end{array}$

$x^{3}-6x^{2}-12x-21+\frac{-32}{x-2}$