Limit cycles for a class of fourth-order differential equations

Abstract

In this article, we study the limit cycles of the fourth-order differential equation

where ϵ is a small enough parameter and is a 2π-periodic function in the variable t.

Keywords:

• limit cycle
• fourth-order differential equation
• perturbation of centres
• averaging theory

AMS Subject Classifications::

• 37G15
• 37D45

Acknowledgement

J. Llibre is partially supported by a MCYT/FEDER grant number MTM03437 and by a CICYT grant number 2009SGR 410.