%% 
%%  A DANTE-Edition example
%% 
%%  Example 05-01-2 on page 58.
%% 
%%  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{201.70511pt}
\setlength\parindent{0pt}

\usepackage{pstricks}

\begin{document}
\begin{pspicture}[showgrid](3,3)
  \pscurve[showpoints=true,linecolor=red,%
     linewidth=1.5pt](0,1)(2,2.5)(3,0)
  \pspolygon[linewidth=0.3pt](0,1)(2,2.5)(3,0)
  \rput[lC]{-105.7}(2,2.5){%
    \psset{linewidth=0.2pt}
    \psline[linestyle=dashed](0,-1)(0,1)
    \psline[linestyle=dashed](0,0)(1.5,0)
    \psarc(0,0){0.25}{0}{90}}
  \uput[-75](0,1){A}
  \uput[135](3,0){B}
  \uput[45](2,2.5){C}
\end{pspicture}
\end{document}