\documentclass[12pt]{article} \usepackage{amssymb,amsmath,amscd,concmath} \pagestyle{empty} \begin{document} \begin{equation*} i\frac{\partial |\psi>}{\partial t}=\left(\begin{array}{ccc} 0 & 0 & \Omega_0^*\cos\left((\omega-\Delta)t\right) \\ 0 & 0 & \Omega_1^*\cos\left((\omega-\Delta)t\right) \\ \Omega_0\cos\left((\omega-\Delta)t\right) & \Omega_1\cos\left((\omega-\Delta)t\right) & \omega \end{array}\right)|\psi>. \end{equation*} \end{document}