Bicuspid Curve

$\begin{figure}\begin{center}\BoxedEPSF{BicuspidalCurve.epsf scaled 700}\end{center}\end{figure}$

The Plane Curve given by the Cartesian equation

$\begin{displaymath} (x^2-a^2)(x-a)^2+(y^2-a^2)^2=0. \end{displaymath}$