\documentclass[12pt]{article}
\usepackage{amssymb,amsmath,amscd,concmath,amsfonts}
\usepackage{color}
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\begin{document}
\begin{equation*}
    u(t) = k_p e(t)+k_i \int_0^t e(\tau) \, d\tau + k_d \frac{de(t)}{dt}
\end{equation*}
\end{document}