Solution of the problem of the center “in the large” for a general quadratic differential system

Driss Boularas (1) , Nicolae Vulpe , Constantin Sergeivitch Sibirskii

1 XLIM-MATHIS - Mathématiques & Sécurité de l'information

Necessary and sufficient conditions of existence of a center in the plane for the "general" quadratic differential systems are given. These conditions are expressed with the affine invariants depending on coefficients of the considered system.

Mots clés: Center-focus problem; qualitative theory of planar differential systems; invariant theory

Domaines: Mathématiques [math]

Driss Boularas, Nicolae Vulpe, Constantin Sergeivitch Sibirskii. Solution of the problem of the center “in the large” for a general quadratic differential system. Differential Equations, 1989, 25 (11). ⟨hal-01315782⟩