$\begin{array}{l}\phantom{\phantom{;}6x^{2}+5;}{\phantom{;}6x^{2}\phantom{-;x^n}-5\phantom{;}\phantom{;}}\\\phantom{;}6x^{2}+5\overline{\smash{)}\phantom{;}36x^{4}\phantom{-;x^n}\phantom{-;x^n}\phantom{-;x^n}+25\phantom{;}\phantom{;}}\\\phantom{\phantom{;}6x^{2}+5;}\underline{-36x^{4}\phantom{-;x^n}-30x^{2}\phantom{-;x^n}\phantom{-;x^n}}\\\phantom{-36x^{4}-30x^{2};}-30x^{2}\phantom{-;x^n}+25\phantom{;}\phantom{;}\\\phantom{\phantom{;}6x^{2}+5-;x^n;}\underline{\phantom{;}30x^{2}\phantom{-;x^n}+25\phantom{;}\phantom{;}}\\\phantom{;\phantom{;}30x^{2}+25\phantom{;}\phantom{;}-;x^n;}\phantom{;}50\phantom{;}\phantom{;}\\\end{array}$

$6x^{2}-5+\frac{50}{5+6x^2}$