Two-dimensional homogeneous cubic systems: classification and normal forms—V

Abstract

This article is the fifth in a series of works devoted to two-dimensional cubic homogeneous systems. It considers a case when a homogeneous polynomial vector in the right-hand part of the system has a linear common factor. A set of such systems is divided into classes of linear equivalence, wherein the simplest system being a third-order normal form is distinguished on the basis of properly introduced principles. Such a form is defined by the matrix of its right-hand part coefficients, which is called the canonical form (CF). Each CF has its own arrangement of non-zero elements, their specific normalization and canonical set of permissible values for the unnormalized elements, which relates CF to the selected class of equivalence. In addition to classification, each CF is provided with: (a) the conditions on the coefficients of the initial system, (b) non-singular linear substitutions that reduce the right-hand part of the system under these conditions to the selected CF, (c) obtained values of CF’s unnormalized elements.