$\begin{array}{l}\phantom{\phantom{;}x\phantom{;}-3;}{\phantom{;}2x^{2}+5x\phantom{;}-10\phantom{;}\phantom{;}}\\\phantom{;}x\phantom{;}-3\overline{\smash{)}\phantom{;}2x^{3}-x^{2}-25x\phantom{;}-12\phantom{;}\phantom{;}}\\\phantom{\phantom{;}x\phantom{;}-3;}\underline{-2x^{3}+6x^{2}\phantom{-;x^n}\phantom{-;x^n}}\\\phantom{-2x^{3}+6x^{2};}\phantom{;}5x^{2}-25x\phantom{;}-12\phantom{;}\phantom{;}\\\phantom{\phantom{;}x\phantom{;}-3-;x^n;}\underline{-5x^{2}+15x\phantom{;}\phantom{-;x^n}}\\\phantom{;-5x^{2}+15x\phantom{;}-;x^n;}-10x\phantom{;}-12\phantom{;}\phantom{;}\\\phantom{\phantom{;}x\phantom{;}-3-;x^n-;x^n;}\underline{\phantom{;}10x\phantom{;}-30\phantom{;}\phantom{;}}\\\phantom{;;\phantom{;}10x\phantom{;}-30\phantom{;}\phantom{;}-;x^n-;x^n;}-42\phantom{;}\phantom{;}\\\end{array}$

$2x^{2}+5x-10+\frac{-42}{x-3}$