%%
%% A DANTE-Edition example
%%
%% Example 30-04-9 on page 608.
%%
%% Copyright (C) 2011 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[]{article}
\pagestyle{empty}
\setlength\textwidth{177.70511pt}
\setlength\parindent{0pt}
\usepackage{pstricks-add}
\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}
