Abstract
The dual of a plane curve in equiaffine geometry is defined as a curve in the space of conics. The image and inverse of this duality are described. It is shown that the duality transforms equiaffine vertices into cusps. As an application, an analogue of Kneser's lemma for osculating conics is proved.
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Dymara, J. Duality for Curves in Affine Plane Geometry. Geometriae Dedicata 79, 189–204 (2000). https://doi.org/10.1023/A:1005275816770
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DOI: https://doi.org/10.1023/A:1005275816770