\nonstopmode
\documentclass[12pt]{article}
\usepackage{cancel}
\pagestyle{empty}
\begin{document}
$$
H(s)={\frac  {c_{0}+c_{1}s+c_{2}s^{2}+c_{3}s^{3}...+c_{m}s^{m}}{d_{0}+d_{1}s+d_{2}s^{2}+...+d_{n}s^{n}}},m\leq n
$$
\end{document}
