\begin{pspicture}(-1,-2.5)(9,2.5)
\psset{xunit=.20mm,yunit=1.75cm}
\psset{plotpoints=50}
\psplot[linestyle=dashed,linecolor=blue]
 {0}{360}{x sin}
\psplot[plotstyle=dots,dotstyle=triangle]
 {0}{360}{x cos}
\psset{plotpoints=200}
\psplot[linecolor=red]{0}{360}
 {x dup sin exch cos mul}
\end{pspicture}