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\begin{document}
\begin{equation*}
   y(t) = Ce^{At} \Bigl( x(0)-(sI-A)^{-1} B \Bigr) + 
           \Bigl( C (sI-A)^{-1} B + D \Bigr) e^{st},  
\end{equation*}
\end{document}