%% 
%%  Ein Beispiel der DANTE-Edition
%%  
%%  1. Auflage
%% 
%%  Beispiel 15-03-5 auf Seite 776.
%% 
%%  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[]{exaarticle}
\pagestyle{empty}
\setlength\textwidth{142.324pt}
\setlength\parindent{0pt}
\usepackage[utf8]{inputenc}
\StartShownPreambleCommands
\usepackage{pstricks-add}
\usepackage{multido}
\StopShownPreambleCommands
\begin{document}
\psscalebox{0.75}{%
\begin{pspicture}(-1,-3)(4.75,3)
 \psaxes{->}(0,0)(-1,-3)(5,3)
 \psplot[polarplot,linewidth=2pt,algebraic,
   plotpoints=500]{0}{6.289}{2*(1+cos(x))}
 \multido{\r=0.000+0.314}{21}{ %
   \psplotTangent[polarplot,Derive=-2*sin(x),
      algebraic,arrows=<->]{\r}{1.5}{2*(1+cos(x))}}
\end{pspicture}}
\end{document}
