Résumé:
Abstract
In this work, we are interested in studying the differential equation with periodic coeffi-
cients of the form :
˙x = A(t)x, x ∈ Rn.
where
A(t + T) = A(t).
We will define some initial concepts related to differential systems with periodic coeffi-
cients, which show us the existence of periodic solutions thanks to two important theories,
Which allow us to convert these periodic systems into fixed systems thanks to a simple
transformation.
