Cocked Hat Curve

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

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

which is similar to the Bicorn.

References

Cundy, H. and Rollett, A. Mathematical Models, 3rd ed. Stradbroke, England: Tarquin Pub., p. 72, 1989.