EU13L-OPG

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$$ x''(t) - x'(t) - 2x(t)=q(t) - t^2,\quad t\in\reel\,.$$

$$ z^2 + 2z + 5\,.$$

$$ \mF=\begin{matr}{rrr} 1 & 4 \\\\ 2 & 5 \\\\ 3 & 6 \end{matr}\,.$$