Authors: Vulpe Nicolae
, Lupan M. N.
The notion of a dicritical (not necessarily singular) point of a quadratic differential system is introduced. As particular cases, it comprises symmetry point of the corresponding integral curves, dicritical nodal singular point and homogeneity point (i.e., such point that the system becomes homogeneous after shifting the point to the origin). Affine-invariant coefficient conditions for determining the number of such points and discerning the phase portraits of quadratic systems with a homogeneity point are given.
Institutul de Matematică al Academiei de Ştiinţe a Moldovei
str. Academiei 5, Chişinău MD-2028, Moldova