%% 
%%  Ein Beispiel der DANTE-Edition
%%  Mathematiksatz mit LaTeX
%%  3. Auflage
%%  Beispiel 04-20-4 auf Seite 75.
%%  Copyright (C) 2018 Herbert Voss
%% 
%%  It may be distributed and/or modified under the conditions
%%  of the LaTeX Project Public License, either version 1.3
%%  of this license or (at your option) any later version.
%%  See http://www.latex-project.org/lppl.txt for details.
%% 
%% ==== 
% Show page(s) 1
%% 
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\documentclass[10pt]{screxa}
\pagestyle{empty}
\setlength\textwidth{352.81416pt}
\setlength\fboxsep{0pt}
\AtBeginDocument{\setlength\parindent{0pt}}
%StartShownPreambleCommands
\newcommand*\Frac[2]{\displaystyle\frac{#1}{#2}}
%StopShownPreambleCommands
\begin{document}
links\rule{1cm}{.5pt} \fbox{$\Frac{A}{B}$} \fbox{\raisebox{0pt}[0pt][0pt]{$\Frac{C}{D}$}}
\fbox{\raisebox{0pt}[0pt][1cm]{$\Frac{E}{F}$}} \fbox{\raisebox{0pt}[1cm][0pt]{$\Frac{G}{H}$}}
\fbox{\raisebox{0pt}[1cm][1cm]{$\Frac{I}{J}$}} \fbox{\raisebox{1cm}[0pt][0pt]{$\Frac{K}{L}$}}
\fbox{\raisebox{-1cm}{$\Frac{M}{N}$}}\rule{1cm}{.5pt}rechts
\end{document}