Bifolium

Bifolium for $a=1.$

For the brachiopod genus, see Bifolium (brachiopod).

The bifolium is a quartic plane curve of the equation:

$(x^2 + y^2)^2 = ax^2y.\,$

In polar coordinates, its equation is

$\rho = a \sin\theta \, \cos^2\theta.$

External links

• http://www.geom.uiuc.edu/~fjw/pisces/docs/models/Bifolium.html
• Bifolium at MathWorld