Louiza Baymout, Rebiha Benterki

Limit Cycles of Piecewise Differential Systems Formed by Linear Center or Focus and Cubic Uniform Isochronous Center

abstract:
Due to the wide interdisciplinary use of discontinuous piecewise differential systems and the main role of the periodic solutions in understanding and explaining many natural phenomena, scientists developed many methods and tools for studying the periodic solutions of such differential systems, like the averaging theory of given order. In this paper, by using the averaging theory up to seven-order for computing the periodic solutions of discontinuous piecewise differential systems, we prove that five is the maximum number of limit cycles that can bifurcate from the discontinuous piecewise differential systems formed by an arbitrary linear focus or center and an arbitrary cubic uniform isochronous center separated by a straight line.

Mathematics Subject Classification: 34C05, 34A34

Key words and phrases: Cubic uniform isochronous center, linear center, limit cycle, averaging theory