SpringerOpen Newsletter

Receive periodic news and updates relating to SpringerOpen.

Open Access Open Badges Research Article

Existence and Uniqueness of Periodic Solution for Nonlinear Second-Order Ordinary Differential Equations

Jian Zu

Author Affiliations

College of Mathematics, Jilin University, Changchun 130012, China

Boundary Value Problems 2011, 2011:192156  doi:10.1155/2011/192156

The electronic version of this article is the complete one and can be found online at: http://www.boundaryvalueproblems.com/content/2011/1/192156

Received:22 May 2010
Accepted:6 March 2011
Published:15 March 2011

© 2011 Jian Zu.

This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

We study periodic solutions for nonlinear second-order ordinary differential problem . By constructing upper and lower boundaries and using Leray-Schauder degree theory, we present a result about the existence and uniqueness of a periodic solution for second-order ordinary differential equations with some assumption.

1. Introduction

The study on periodic solutions for ordinary differential equations is a very important branch in the differential equation theory. Many results about the existence of periodic solutions for second-order differential equations have been obtained by combining the classical method of lower and upper solutions and the method of alternative problems (The Lyapunov-Schmidt method) as discussed by many authors [110]. In [11], the author gives a simple method to discuss the existence and uniqueness of nonlinear two-point boundary value problems. In this paper, we will extend this method to the periodic problem.

We consider the second-order ordinary differential equation


Throughout this paper, we will study the existence of periodic solutions of (1.1) with the following assumptions:

are continuous in , and



where is some positive integer,


The following is our main result.

Theorem 1.1.

Assume that and hold, then (1.1) has a unique periodic solution.

2. Basic Lemmas

The following results will be used later.

Lemma 2.1 (see [12]).

Let with




and the constant is optimal.

Lemma 2.2 (see [12]).

Let with the boundary value conditions , then


Consider the periodic boundary value problem


Lemma 2.3.

Suppose that are -integrable periodic function, where satisfy the condition (H2), with


then (2.4) has only the trivial -periodic solution .


If on the contrary, (2.4) has a nonzero -periodic solution , then using (2.4), we have


where is undetermined.

Firstly, we prove that has at least one zero in . If , we may assume . Since is a -periodic solution, there exists a with . Then,


we could get a contradiction.

Without loss of generality, we may assume that ; then there exists a sufficiently small such that . Since is a continuous function, there must exist a with .

Secondly, we prove that has at least zeros on . Considering the initial value problem




is the solution of (2.8) and


where with . Since


holds under the assumptions of , there is a , such that


Now, let . By the conditions (H2), (2.11), and (2.12), we have



Since is decreasing in , we have . Therefore,


We also consider the initial value problem




is the solution of (2.16), where is the same as the previous one, and


Hence, there exists a with , such that




From (2.12) and (2.19), it follows that


By and (2.21), we have


Since is decreasing on , we have , and


We now prove that has a zero point in . If on the contrary for , then we would have the following inequalities:



In fact, from(2.4), (2.8), and (2.15), we have


with . Setting , and since


we obtain


Notice that , which implies


So, we have


Integrating from 0 to , we obtain




which implies (2.24). By a similar argument, we have (2.25). Therefore, , a contradiction, which shows that has at least one zero in , with .

We let . If , then from a similar argument, there is a , such that and so on. So, we obtain that has at least zeros on .

Thirdly, we prove that has at least zeros on . If, on the contrary, we assume that only has zeros on , we write them as




Without loss of generality, we may assume that . Since


we obtain , which contradicts . Therefore, has at least zeros on .

Finally, we prove Lemma 2.3. Since has at least zeros on , there are two zeros and with . By Lemmas 2.1 and 2.2, we have


From , it follows that




which implies for . Also . Therefore, for, a contradiction. The proof is complete.

3. Proof of Theorem 1.1

Firstly, we prove the existence of the solution. Consider the homotopy equation


where and . When , it holds (1.1). We assume that is the fundamental solution matrix of with . Equation (3.1) can be transformed into the integral equation


From , is a periodic solution of (3.2), then


For is invertible,


We substitute (3.4) into (3.2),


Define an operator


such that


Clearly, is a completely continuous operator in .

There exists , such that every possible periodic solution satisfies ( denote the usual normal in . If not, there exists and the solution with .

We can rewrite (3.1) in the following form:


Let , obviously . It satisfies the following problem:


in which we have


Since , are uniformly bounded and equicontinuous, there exists continuous function , and a subsequence of (denote it again by ), such that ,  uniformly in . Using and , and are uniformly bounded. By the Hahn-Banach theorem, there exists integrable function ,, and a subsequence of (denote it again by ), such that


where denotes "weakly converges to" in . As a consequence, we have


that is,


Denote that , , then we get


which also satisfy the condition . Notice that and are integrable on , so satisfies Lemma 2.3. Hence, we have , which contradicts . Therefore, is bounded.



Because for , by Leray-Schauder degree theory, we have


So, we conclude that has at least one fixed point in , that is, (1.1) has at least one solution.

Finally, we prove the uniqueness of the equation when the condition and holds. Let and be two -periodic solutions of the problem. Denote , then is a solution of the following problem:


By Lemma 2.3, we have for .

Let . We have


with . Denote by . So, is the solution of the problem (1.1). The proof is complete.

4. An Example

Consider the system


where is a continuous function. Obviously,


satisfy Theorem 1.1, then there is a unique -periodic solution in this system.


The author expresses sincere thanks to Professor Yong Li for useful discussion. He would like to thank the reviewers for helpful comments on an earlier draft of this paper.


  1. Bereanu, C, Mawhin, J: Existence and multiplicity results for some nonlinear problems with singular -Laplacian. Journal of Differential Equations. 243(2), 536–557 (2007). Publisher Full Text OpenURL

  2. Ehme, J, Eloe, PW, Henderson, J: Upper and lower solution methods for fully nonlinear boundary value problems. Journal of Differential Equations. 180(1), 51–64 (2002). Publisher Full Text OpenURL

  3. Kannan, R, Lakshmikantham, V: Existence of periodic solutions of nonlinear boundary value problems and the method of upper and lower solutions. Applicable Analysis. 17(2), 103–113 (1983)

  4. Knobloch, H-W: On the existence of periodic solutions for second order vector differential equations. Journal of Differential Equations. 9, 67–85 (1971)

  5. Knobloch, HW, Schmitt, K: Non-linear boundary value problems for systems of differential equations. Proceedings of the Royal Society of Edinburgh. Section A. 78(1-2), 139–159 (1977)

  6. Liu, Y, Ge, W: Positive periodic solutions of nonlinear Duffing equations with delay and variable coefficients. Tamsui Oxford Journal of Mathematical Sciences. 20(2), 235–255 (2004)

  7. Ortega, R, Tarallo, M: Almost periodic upper and lower solutions. Journal of Differential Equations. 193(2), 343–358 (2003). Publisher Full Text OpenURL

  8. Rachůnková, I, Tvrdý, M: Existence results for impulsive second-order periodic problems. Nonlinear Analysis. Theory, Methods & Applications. 59(1-2), 133–146 (2004). PubMed Abstract | Publisher Full Text OpenURL

  9. Schmitt, K: Periodic solutions of linear second order differential equations with deviating argument. Proceedings of the American Mathematical Society. 26, 282–285 (1970). Publisher Full Text OpenURL

  10. Sędziwy, S: Nonlinear periodic boundary value problem for a second order ordinary differential equation. Nonlinear Analysis. Theory, Methods & Applications. 32(7), 881–890 (1998). PubMed Abstract | Publisher Full Text OpenURL

  11. Li, Y: Boundary value problems for nonlinear ordinary differential equations. Northeastern Mathematical Journal. 6(3), 297–302 (1990)

  12. Mitrinović, DS: Analytic Inequalities,p. xii+400. Springer, New York, NY, USA (1970)