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\usepackage{amssymb, amsmath}
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\usepackage[ngerman]{babel}
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\usepackage[margin=2.5cm]{geometry}
\usepackage{hyperref}
\usepackage{color}
\usepackage{framed}
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\hypersetup{
pdfauthor = {Martin Thoma},
pdfkeywords = {German-English mathematics dictionary},
pdftitle = {German-English mathematics dictionary}
}
\begin{document}
\section{A}
\underline{abgeschlossen} (adj.) closed
\section{P}
\underline{punktsymmetrisch} (adj.) centrally symmetric
\section{S}
\underline{streng monoton fallend} (adj.) strictly monotonically decreasing
\underline{streng monoton wachsend} strictly monotonically increasing
\end{document}