Résumé:
We study the averaging method of some differential
systems with non-linear center.
To understand more about this method, we recall
some of the basic concepts and theorems. We start by
defining differential equations, limit cycles,…down to
the averaging method of some differential systems
with linear center.
Then, we briefly mention some of the previously
proposed proofs and results for both cases, the
stability of the orbits and the nature of their center
(linear or non-linear).
