% cusp.tex
%
% Singular curve y^2 = x^3 over the real numbers
%
% Author: Peter Schwabe
% Public domain

\psset{xunit=8cm, yunit=4cm} 
  \begin{pspicture}(-0.2,-1)(1,1) 
  \psaxes[Dx=.2, Dy=.2]{->}(0,0)(-0.2,-1)(1,1)  
  
\psplot[plotstyle=curve]{0}{1}{x x mul x mul sqrt neg}
\psplot[plotstyle=curve]{0}{1}{x x mul x mul sqrt}

\end{pspicture}