In this paper we study the limit cycles of the Liénard differential system of the form over(x, ̈) + f (x) over(x, ̇) + g (x) = 0, or its equivalent system over(x, ̇) = y - F (x), over(y, ̇) = - g (x). We provide sufficient conditions in order that the system exhibits at least n or exactly n limit cycles. © 2007 Elsevier Inc. All rights reserved.
- Limit cycles
- Liénard polynomial vector fields
- Liénard systems