\documentclass[12pt]{article} \usepackage{amssymb,amsmath,amscd,concmath,amsfonts} \usepackage{color} \pagestyle{empty} \begin{document} \begin{equation*} y(t) = C e^{At} x(0) + \int_0^t C e^{A(t-\tau)}B u(\tau) d\tau + Du(t). \end{equation*} \end{document}