\documentclass[12pt,a4paper]{article}% Herbert Voss 2005-11-23
\usepackage{pstricks,pstricks-add}
\pagestyle{empty}

\begin{document}

\def\pshlabel#1{\footnotesize#1}
\def\psvlabel#1{\footnotesize#1}
\psset{unit=0.5cm}
\begin{pspicture}*(-5.1,-5.1)(3.1,3.1)
  \psaxes[labelsep=.75mm,ticksize=2pt,arrowlength=1.75,linewidth=0.17mm]%
      {->}(0,0)(-4.99,-4.99)(3,3)
  \uput[-90](3,0){$x$}
  \uput[0](0,3){$y$}
  \rput[Br](-.15,-.35){$0$}
  \psset{linewidth=.35mm,polarplot=true}
  \def\Func{neg x sin mul x cos mul x sin 3 exp x cos 3 exp add div}
  \psplot[linecolor=red]{140}{310}{3 \Func}
  \psplot[linecolor=cyan]{140}{310}{6 \Func}
  \psplot[linecolor=blue]{140}{310}{9 \Func}
\end{pspicture}
\quad
\psset{unit=1cm}
\begin{pspicture}(-2.5,-2.5)(2.5,2.5)% Ulrich Dirr
 \psaxes[labelsep=.75mm,arrowlength=1.75,%
    ticksize=2pt,linewidth=0.17mm]{->}(0,0)(-2,-2)(2,2)
  \uput[-90](2,0){$x$}
  \uput[0](0,2){$y$}
  \rput[Br](-.15,-.35){$0$}
  \psset{linewidth=.35mm,plotstyle=curve,polarplot=true}
  \psplot[linecolor=red]{0}{360}{x cos 2 mul x sin mul}
  \psplot[linecolor=green]{0}{360}{x cos 3 mul x sin mul}
  \psplot[linecolor=blue]{0}{360}{x cos 4 mul x sin mul}
\end{pspicture}

\end{document}
