\documentclass{article} \usepackage{amsmath} \usepackage{amssymb} \usepackage{amsfonts} \thispagestyle{empty} \begin{document} \begin{equation} S(r)=S_0(1+\frac{r^2}{r_c^2})^{-3\beta+1/2}+bkg\notag \end{equation} \end{document}