Limit Cycles of Quadratic Systems with a Perturbed Weak Focus of Third Order and Saddle Equilibrium at Infinity
نویسندگان
چکیده
In this paper, we develop a modification of the method of asymptotic integration of Liénard systems and propose an analytical-numerical procedure making it possible to extend the domain of coefficients corresponding to the existence of a limit cycle in a quadratic system with a weak focus of order 3 (for which small perturbations of coefficients yield four limit cycles).
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