The Negative Pedal Curve (NPC) of the Ellipse with respect to a boundary point M is a 3-cusp deltoid which is the affine image of the Steiner Curve . Over all M the family has invariant area and displays an array of interesting properties.
The Negative Pedal Curve (NPC) of the Ellipse with respect to a boundary point M is a 3-cusp closed-curve which is the affine image of the Steiner Deltoid . Over all M the family has invariant area and displays an array of interesting properties.
R
deltoid
closed-curve
R
Curve
Deltoid