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IMCS/Publications/BASM/Issues/BASM n.1 (29), 1999/

Real quadratic systems with two imaginary invariant straight lines. (English)

Authors: Voldman M., Vulpe Nicolae

Abstract

Affine invariant coefficient conditions for quadratic system to possess two conjugate imaginary straight line solutions as well as two couples of such lines as solutions are established. For some classes of quadratic systems with two imaginary invariant straight lines the necessary and sufficient affine invariant conditions for possessing just one limit cycle are determined.

Academy of Science of Moldova
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