%%
%%  Ein Beispiel der DANTE-Edition
%%
%%  7. Auflage
%%
%%  Beispiel 29-03-5 auf Seite 641.
%%
%%  Copyright (C) 2016 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
%%
%%
\documentclass[]{exaarticle}
\pagestyle{empty}
\setlength\textwidth{145.16928pt}
\setlength\parindent{0pt}
%StartShownPreambleCommands
\usepackage{pstricks-add}
%StopShownPreambleCommands
\begin{document}
\def\Func{10 x div}\psset{unit=0.75}
\begin{pspicture}(-0.5,-0.5)(6.25,6.5)
 \psaxes[arrowscale=1.5]{->}(6.25,6.25)
 \psplot[linewidth=2pt,algebraic]{1.6}{5}{10/x}
 \psplotTangent[linewidth=.5pt,linecolor=red,
   algebraic]{3}{2}{10/x}
 \psplotTangent[linewidth=.5pt,linecolor=blue,
   algebraic,Derive=(x*x)/10]{3}{2}{10/x}
 \psline[linestyle=dashed](!0 /x 3 def \Func)%
   (!3 /x 3 def \Func)(3,0)
\end{pspicture}
\end{document}