Approximating solutions of nonlinear periodic boundary value … · Approximating solutions of nonlinear periodic boundary value problems with maxima ... nonlinear differential equations

Dhage, Cogent Mathematics (2016), 3: 1206699http://dx.doi.org/10.1080/23311835.2016.1206699

COMPUTATIONAL SCIENCE | RESEARCH ARTICLE

Approximating solutions of nonlinear periodic boundary value problems with maximaBapurao C. Dhage1*

Abstract: In this paper we study a periodic boundary value problem of first order nonlinear differential equations with maxima and discuss the existence and approximation of the solutions. The main result relies on the Dhage iteration method embodied in a recent hybrid fixed point theorem of Dhage (2014) in a partially ordered normed linear space. At the end, we give an example to illustrate the applicability of the abstract results to some concrete periodic boundary value problems of nonlinear differential equations.

Subjects: Advanced Mathematics; Analysis - Mathematics; Applied Mathematics; Differential Equations; Mathematics & Statistics; Non-Linear Systems; Operator Theory; Science

Keywords: differential equations with maxima; Dhage iteration method; approximation of solutions

AMS Subject Classifications: 34A12; 34A45; 47H07; 47H10

1. IntroductionThe study of fixed point theorems for the contraction mappings in partially ordered metric spaces is ini-tiated by Ran and Reurings (2004) which is further continued by Nieto and Rodringuez-Lopez (2005) and applied to periodic boundary value problems of nonlinear first order ordinary differential equations for proving the existence results under certain monotonic conditions. Similarly, the study of hybrid fixed point theorems in a partially ordered metric space is initiated by Dhage (2013, 2014, 2015a) with applications to nonlinear differential and integral equation under weaker mixed conditions of nonlin-earities. See Dhage (2015b, 2015c) and the references therein. In this paper we investigate the exist-ence of approximate solutions of certain hybrid differential equations with maxima using the Dhage iteration method embodied in a hybrid fixed point theorem. We claim that the results of this paper are new to the theory of nonlinear differential equations with maxima.

Corresponding author: Bapurao C. Dhage, Kasubai, Gurukul Colony, Dist. Latur, Ahmedpur 413515, Maharashtra, IndiaE-mail: [email protected]

Reviewing editor:Shaoyong Lai, Southwestern University of Finance and Economics, China

Additional information is available at the end of the article

ABOUT THE AUTHORThe author of this paper is a nonlinear analyst always engaged in the investigation of new technique or method for studying the nonlinear equations in different abstract spaces under different situations. He has also a keen interest in the study of numerical or approximate solutions of nonlinear differential and integral equations. He deals with and claims that the periodic BVPs of first and second order ordinary nonlinear differential equations an easily be analyzed under minimum natural conditions for numerical or approximate and other qualitative aspects of the solutions.

PUBLIC INTEREST STATEMENTMany of the natural and physical processes of the universe are governed by periodic boundary value problems of nonlinear differential equations. Therefore, the results of this paper are useful to scientists and mathematicians to describe some universal phenomena in a scientific manner for better conclusion. Again the Dhage iteration principle which has been used in this paper is a powerful technique for nonlinear equations and so other researchers of dynamic systems and applications may explore this new technique to tackle different nonlinear problems for qualitative analysis and applications.

Received: 14 February 2016Accepted: 14 June 2016First Published: 30 June 2016

© 2016 The Author(s). This open access article is distributed under a Creative Commons Attribution (CC-BY) 4.0 license.

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Given a closed and bounded interval J = [0, T] of the real line ℝ for some T > 0, we consider the following hybrid differential equation (in short HDE) of first order periodic boundary value problems,

for all t ∈ J = [0, T] and f ,g : J ×ℝ → ℝ are continuous functions.

By a solution of Equation (1.1) we mean a function x ∈ C1(J,ℝ) that satisfies Equation (1.1), where C1(J,ℝ) is the space of continuously differentiable real-valued functions defined on J.

Differential equations with maxima are often met in the applications, for instance in the theory of automatic control. Numerous results on existence and uniqueness, asymptotic stability as well as numerical solutions for such equations have been obtained. To name a few, we refer the reader to (Bainov & Hristova, 2011; Otrocol, 2014) and the references therein. The PBVP’s of nonlinear first order ordinary differential equations have also been a topic of great interest since long time. The HDE (1.1) is a linear perturbation of first type of the PBVP of first order nonlinear differential equations. The de-tails of different types of perturbation appears in Dhage (2010). The special cases of the HDE (1.1) are

and

The HDE (1.2) has already been discussed in the literature for different aspects of the solutions using usual Picard as well as Dhage iteration method. See Zeidler (1986) and Dhage and Dhage (2015a). Similarly, the HDE (1.3) has been studied earlier using Picard method. See Bainov, and Hristova (2011) and the references therein. Very recently, Dhage and Octrocol (2016) have initiated the study of initial value problems of first order ordinary nonlinear differential equations via new Dhage iteration method, however to the best of author’s knowledge the HDE (1.3) is not discussed via Dhage iteration method. Therefore, the HDE (1.1) is new to the literature in the set up of Dhage iteration method. In this paper we discuss the HDE (1.1) for existence and approximation of the solu-tions via a new approach based upon Dhage iteration method which include the existence and ap-proximation results for the HDEs (1.2) and (1.3) as special cases which are again new to the theory of differential equations.

In the following section we give some preliminaries and the key tool that will be used for proving the main result of this paper.

2. PreliminariesThroughout this paper, unless otherwise mentioned, let (E,⪯, ‖ ⋅ ‖) denote a partially ordered nor-med linear space. Two elements x and y in E are said to be comparable if either the relation x ⪯ or y ⪯ x holds. A non-empty subset C of E is called a chain or totally ordered if all the elements of C are comparable. It is known that E is regular if {xn} is a nondecreasing (resp. nonincreasing) sequence in E such that xn → x∗ as n→ ∞, then xn ⪯ x

∗ (resp. xn ⪰ x∗) for all n ∈ ℕ. The conditions guaranteeing

the regularity of E may be found in Heikkilä and Lakshmikantham (1994) and the references therein.

We need the following definitions (see Dhage, 2013, 2014 and the references therein) in what follows.

(1.1)

⎧⎪⎨⎪⎩

x�(t) = f (t, x(t)) + g

�t,max0≤�≤t

x(�)

�,

x(0) = x(T),

(1.2)

{x�(t) = f (t, x(t)), t ∈ J,

x(0) = x(T),

(1.3)

⎧⎪⎨⎪⎩

x�(t) = g

�t,max0≤�≤t

x(�)

�, t ∈ J,

x(0) = x(T).

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Definition 2.1 A mapping : E → E is called isotone or monotone nondecreasing if it preserves the order relation ⪯, that is, if x ⪯ y implies x ⪯ y for all x, y ∈ E. Similarly, is called monotone nonin-creasing if x ⪯ y implies x ⪰ y for all x, y ∈ E. Finally, is called monotonic or simply monotone if it is either monotone nondecreasing or monotone nonincreasing on E.

Definition 2.2 A mapping : E → E is called partially continuous at a point a ∈ E if for 𝜖 > 0 there ex-ists a 𝛿 > 0 such that ‖ x − a‖ < 𝜖 whenever x is comparable to a and ‖x − a‖ < 𝛿. called partially continuous on E if it is partially continuous at every point of it. It is clear that if is partially continu-ous on E, then it is continuous on every chain C contained in E.

Definition 2.3 A non-empty subset S of the partially ordered Banach space E is called partially bounded if every chain C in S is bounded. An operator on a partially normed linear space E into itself is called partially bounded if (E) is a partially bounded subset of E. is called uniformly partially bounded if all chains C in (E) are bounded by a unique constant.

Definition 2.4 A non-empty subset S of the partially ordered Banach space E is called partially com-pact if every chain C in S is a relatively compact subset of E. A mapping : E → E is called partially compact if (E) is a partially relatively compact subset of E. is called uniformly partially compact if is a uniformly partially bounded and partially compact operator on E. is called partially totally bounded if for any bounded subset S of E, (S) is a partially relatively compact subset of E. If is par-tially continuous and partially totally bounded, then it is called partially completely continuous on E.

Remark 2.1 Suppose that is a nondecreasing operator on E into itself. Then is a partially bound-ed or partially compact if (C) is a bounded or relatively compact subset of E for each chain C in E.

Definition 2.5 The order relation ⪯ and the metric d on a non-empty set E are said to be compatible if {xn} is a monotone sequence, that is, monotone nondecreasing or monotone nonincreasing se-quence in E and if a subsequence {xnk} of {xn} converges to x∗ implies that the original sequence {xn} converges to x∗. Similarly, given a partially ordered normed linear space (E,⪯, ‖ ⋅ ‖), the order relation ⪯ and the norm ‖ ⋅ ‖ are said to be compatible if ⪯ and the metric d defined through the norm ‖ ⋅ ‖ are compatible. A subset S of E is called Janhavi if the order relation ⪯ and the metric d or the norm ‖ ⋅ ‖ are compatible in it. In particular, if S = E, then E is called a Janhavi metric or Janhavi Banach space.

Clearly, the set ℝ of real numbers with usual order relation ≤ and the norm defined by the absolute value function | ⋅ | has this property. Similarly, the finite dimensional Euclidean space ℝn with usual componentwise order relation and the standard norm possesses the compatibility property and so is a Janhavi Banach space.

Definition 2.6 An upper semi-continuous and monotone nondecreasing function � :ℝ+→ ℝ

+ is

called a -function provided �(0) = 0. An operator : E → E is called partially nonlinear -contrac-tion if there exists a -function � such that

for all comparable elements x, y ∈ E, where 0 < 𝜓(r) < r for r > 0. In particular, if �(r) = k r, k > 0, is called a partial Lipschitz operator with a Lischitz constant k and moreover, if 0 < k < 1, is called a partial linear contraction on E with a contraction constant k.

The Dhage iteration method embodied in the following applicable hybrid fixed point theorem of Dhage (2014) in a partially ordered normed linear space is used as a key tool for our work contained in this paper. The details of a Dhage iteration method is given in Dhage (2015b, 2015c), Dhage, Dhage, and Graef (2016) and the references therein.

(2.1)‖ x − y‖ ≤ �(‖x − y‖)

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Theorem 2.1 (Dhage, 2014) Let (E,⪯, ‖ ⋅ ‖) be a regular partially ordered complete normed linear space such that every compact chain C of E is Janhavi. Let ,: E → E be two nondecreasing opera-tors such that

(a) is partially bounded and partially nonlinear -contraction,

(b) is partially continuous and partially compact, and

(c) there exists an element x0 ∈ E such that x0 ⪯ x0 + x0 or x0 ⪰ x0 + x0.Then the operator equation x + x = x has a solution x∗ in E and the sequence {xn} of successive iterations de-fined by xn+1 = xn + xn, n = 0,1,..., converges monotonically to x∗.

Remark 2.2 The condition that every compact chain of E is Janhavi holds if every partially compact subset of E possesses the compatibility property with respect to the order relation ⪯ and the norm ‖ ⋅ ‖ in it.

Remark 2.3 We remark that hypothesis (a) of Theorem 2.1 implies that the operator is partially continuous and consequently both the operators and in the theorem are partially continuous on E. The regularity of E in above Theorem 2.1 may be replaced with a stronger continuity condition of the operators and on E which is a result proved in Dhage (2013, 2014).

3. Main resultsIn this section, we prove an existence and approximation result for the HDE (1.1) on a closed and bounded interval J = [0, T] under mixed partial Lipschitz and partial compactness type conditions on the nonlinearities involved in it. We place the HDE (1.1) in the function space C(J,ℝ) of continuous real-valued functions defined on J. We define a norm ‖ ⋅ ‖ and the order relation ≤ in C(J,ℝ) by

and

Clearly, C(J,ℝ) is a Banach space with respect to above supremum norm and also partially ordered w.r.t. the above partially order relation ≤. It is known that the partially ordered Banach space C(J,ℝ) is regular and lattice so that every pair of elements of E has a lower and an upper bound in it. The following useful lemma concerning the Janhavi subsets of C(J,ℝ) follows immediately form the Arzelá-Ascoli theorem for compactness.

Lemma 3.1 Let �C(J,ℝ),≤, ‖ ⋅ ‖� be a partially ordered Banach space with the norm ‖ ⋅ ‖ and the order re-

lation ≤ defined by (3.1) and (3.2) respectively. Then every partially compact subset of C(J,ℝ) is Janhavi.

Proof The proof of the lemma is well-known and appears in the works of Dhage (2015b, 2015c), Dhage and Dhage (2014), Dhage et al. (2016) and so we omit the details. □

The following useful lemma is obvious and may be found in Dhage (2008) and Nieto (1997).

Lemma 3.2 For any function � ∈ L1(J,ℝ), x is a solution to the differential equation

if and only if it is a solution of the integral equation

(3.1)‖x‖ = supt∈J

�x(t)�

(3.2)x ≤ y ⟺ x(t) ≤ y(t) for all t ∈ J.

(3.3)x�(t) + �x(t) = �(t), t ∈ J,

x(0) = x(T),

}

(3.4)x(t) =

∫

T

0

G�(t, s) �(s)ds

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where,

Notice that the Green’s function G� is continuous and nonnegative on J × J and therefore, the

number

exists for all � ∈ ℝ+. For the sake of convenience, we write G

�(t, s) = G(t, s) and K

�= K.

Another useful result for establishing the main result is as follows.

Lemma 3.3 If there exists a differentiable function u ∈ C(J,ℝ) such that

for all t ∈ J, where � ∈ ℝ, 𝜆 > 0 and � ∈ L1(J,ℝ), then

for all t ∈ J, where G(t, s) is a Green’s function given by (3.5).

Proof Suppose that the function u ∈ C(J,ℝ) satisfies the inequalities given in (3.6). Multiplying the first inequality in (3.6) by e�t,

A direct integration of above inequality from 0 to t yields

for all t ∈ J. Therefore, in particular,

Now u(0) ≤ u(T), so one has

From (3.9) and (3.10) it follows that

which further yields

Substituting (3.12) in (3.8) we obtain

(3.5)G𝜆(t, s) =

{e𝜆s−𝜆t+𝜆T

e𝜆T−1, if 0 ≤ s ≤ t ≤ T,

e𝜆s−𝜆t

e𝜆T−1, if 0 ≤ t < s ≤ T.

K�: = max {|G

�(t, s)| : t, s ∈ [0, T]}

(3.6)u�(t) + �u(t) ≤ �(t), t ∈ J,

u(0) ≤ u(T),

}

(3.7)u(t) ≤�

T

0

G(t, s) �(s)ds,

(e�tu(t)

)�≤ e�t�(t).

(3.8)e�tu(t) ≤ u(0) +�

t

0

e�s�(s)ds,

(3.9)e�Tu(T) ≤ u(0) +�

T

0

e�s�(s)ds.

(3.10)u(0)e�T ≤ u(T)e�T .

(3.11)e�Tu(0) ≤ u(0) +�

T

0

e�s�(s)ds

(3.12)u(0) ≤�

T

0

e�s

(e�T − 1)�(s)ds.

u(t) ≤�

T

0

G(t, s)�(s)ds,

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for all t ∈ J. This completes the proof. □

We need the following definition in what follows.

Definition 3.1 A function u ∈ C1(J,ℝ) is said to be a lower solution of the Equation (1.1) if it satisfies

for all t ∈ J. Similarly, a differentiable function v ∈ C1(J,ℝ) is called an upper solution of the HDE (1.1) if the above inequality is satisfied with reverse sign.

We consider the following set of assumptions in what follows:

(H1) There exist constants 𝜆 > 0,𝜇 > 0 with � ≥ � such that

for all t ∈ J and x, y ∈ ℝ, x ≥ y. Moreover, 𝜆K T < 1.

(H2) There exists a constant Mg > 0 such that ‖g(t, x)‖ ≤ Mg, for all t ∈ J, x ∈ ℝ;

(H3) g(t, x) is nondecreasing in x for each t ∈ J.

(H4) HDE (1.1) has a lower solution u ∈ C1(J,ℝ).

Now we consider the following HDE

for all t ∈ J = [0, T], where �f (t, x) = f (t, x) + 𝜆x, 𝜆 > 0.

Remark 3.1 A function u ∈ C1(J,ℝ) is a solution of the HDE (3.13) if and only if it is a solution of the HDE (1.1) defined on J.

We also consider the following hypothesis in what follows.

(H5) There exists a constant M�f > 0 such that ‖‖‖f̃ (t, x)‖‖‖ ≤ Mf̃ for all t ∈ J and x ∈ ℝ.

Lemma 3.4 Suppose that the hypotheses (H2), (H3) and (H5) hold. Then a function x ∈ C(J,ℝ) is a solu-tion of the HDE (3.3) if and only if it is a solution of the nonlinear hybrid integral equation (in short HIE)

for all t ∈ J.

Theorem 3.1 Suppose that hypotheses (H1) − (H5) hold. Then the HDE (1.1) has a solution x∗ defined on J and the sequence {xn} of successive approximations defined by

⎧⎪⎨⎪⎩

u�(t) ≤ f (t,u(t)) + g

�t,max0≤�≤t

u(�)

�,

u(0) ≤ u(T),

(∗)

0 ≤ [f (t, x) + �x] − [f (t, y) + �y] ≤ �(x − y)

(3.13)

⎧⎪⎨⎪⎩

x�(t) + �x(t) = f̃ (t, x(t)) + g

�t,max0≤�≤t

u(�)

�,

x(0) = x(T),

(3.14)x(t) =�

T

0

G(t, s)f̃ (s, x(s))ds +�

T

0

G(t, s)g

(s,max

0≤�≤sx(�)

)ds,

Page 7 of 12


for all t ∈ J, converges monotonically to x∗.

Proof Set E = C(J,ℝ). Then, in view of Lemma 3.1, every compact chain C in E possesses the compat-ibility property with respect to the norm ‖ ⋅ ‖ and the order relation ≤ so that every compact chain C is Janhavi in E.

Define two operators and on E by

and

From the continuity of the integral, it follows that and define the operators ,: E → E. Applying Lemma (3.4), the HDE (1.1) is equivalent to the operator equation

Now, we show that the operators and satisfy all the conditions of Theorem 2.1 in a series of fol-lowing steps.

Step I: and are nondecreasing on E.

Let x, y ∈ E be such that x ≥ y. Then by hypothesis (H1), we get

for all t ∈ J.

Next, we show that the operator is also nondecreasing on E. Let x, y ∈ E be such that x ≥ y. Then x(t) ≥ y(t) for all t ∈ J. Since y is continuous on [0, t], there exists a �∗ ∈ [a, t] such that y(�∗) = max

a≤�≤ty(�).

By definition of ≤, one has x(�∗) ≥ y(�∗). Consequently, we obtain

Now, using hypothesis (H3), it can be shown that the operator is also nondecreasing on E.

Step II: is partially bounded and partially contraction on E.

Let x ∈ E be arbitrary. Then by (H5) we have

(3.15)

x0 = u,

xn+1(t) = �

T

0

G(t, s)f̃ (s, xn(s))ds

+�

T

0

G(t, s)g

(s,max

0≤�≤sxn(�)

)ds,

(3.16)x(t) =�

T

0

G(t, s)f̃ (s, x(s))ds, t ∈ J,

(3.17)x(t) =�

T

0

G(t, s)g

(s,max

0≤�≤sx(�)

)ds, t ∈ J.

x(t) + x(t) = x(t), t ∈ J.

x(t) =�

T

0

G(t, s)f̃ (s, x(s))ds

≥�

T

0

G(t, s)f̃ (s, y(s))ds

= y(t),

maxa≤�≤t

x(�) = x(�∗) ≥ y(�∗) = maxa≤�≤t

y(�).

Page 8 of 12


for all t ∈ J. Taking the supremum over t, we obtain ‖x(t)‖ ≤ Mf̃ K T and so, is a bounded operator on E. This implies that is partially bounded on E. Let x, y ∈ E be such that x ≥ y. Then by (H1) we have

for all t ∈ J. Taking the supremum over t, we obtain ‖x −y‖ ≤ L‖x − y‖ for all x, y ∈ E with x ≥ y, where L = 𝜆K T < 1. Hence is a partially contraction on E and which also implies that is partially continuous on E.

Step III: is partially continuous on E.

Let {xn}n∈ℕ be a sequence in a chain C such that xn → x, for all n ∈ ℕ. Then

for all t ∈ J. This shows that xn converges monotononically to x pointwise on J.

Now we show that {xn}n∈ℕ is an equicontinuous sequence of functions in E.

Let t1, t2 ∈ J with t1 < t2. We have

‖x(t)‖ ≤�

T

0

G(t, s)��f̃ (s, x(s))

��ds

≤ Mf̃ �

T

0

G(t, s)ds

≤ Mf̃ K T,

‖x(t) −y(t)‖ ≤

��T

0

G(t, s)�f̃ (s, x(s)) − f̃ (s, y(s))

�ds

��≤�

T

0

G(t, s)�‖x(s) − y(s)‖ds

≤�

T

0

G(t, s)�‖x(s) − y(s)‖ds

≤ ��

T

0

G(t, s)‖x − y‖ds≤ �K T ‖x − y‖,

limn→∞

xn(t) = limn→∞ �

T

0

G(t, s)g

(s,max

0≤�≤sxn(�)

)ds

=�

T

0

G(t, s)

[limn→∞

g

(s,max

0≤�≤sxn(�)

)]ds

=�

T

0

G(t, s)g

(s,max

0≤�≤sxn(�)

)ds

= x(t),

‖‖Bxn(t2) − xn(t1)‖‖ =

‖‖‖‖‖�T

0

G(t2, s)g

(s,max

0≤�≤sxn(�)

)ds

−�

T

0

G(t1, s)g

(s,max

0≤�≤sxn(�)

)ds

‖‖‖‖‖≤�

T

0

‖‖G(t2, s) − G(t1, s)‖‖‖‖‖‖‖g

(s,max

0≤�≤sxn(�)

)ds

‖‖‖‖‖≤ Mg �

T

0

||G(t2, s) − G(t1, s)||ds→ 0 as t

2→ t

1,

Page 9 of 12


uniformly for all n ∈ ℕ. This shows that the convergence xn → x is uniform and hence is partially continuous on E.

Step IV: is partially compact operator on E.

Let C be an arbitrary chain in E. We show that (C) is uniformly bounded and equicontinuous set in E. First we show that (C) is uniformly bounded. Let y ∈ (C) be any element. Then there is an ele-ment x ∈ C such that y = x. By hypothesis (H2)

for all t ∈ J. Taking the supremum over t we obtain ‖y‖ ≤ ‖x‖ ≤ r, for all y ∈ (C). Hence (C) is uniformly bounded subset of E. Next we show that (C) is an equicontinuous set in E. Let t1, t2 ∈ J, with t1 < t2. Then, for any y ∈ (C), one has

uniformly for all y ∈ (C). This shows that (C) is an equicontinuous subset of E. So (C) is a uni-formly bounded and equicontinuous set of functions in E. Hence it is compact in view of Arzelá-Ascoli theorem. Consequently : E → E is a partially compact operator of E into itself.

Step V: u satisfies the inequality u ≤ u + u.

By hypothesis (H4) the Equation (1.1) has a lower solution u defined on J. Then we have

A direct application of lemma 3.3 yields that

for t ∈ J. From definitions of the operators and it follows that u(t) ≤ u(t) + u(t), for all t ∈ J. Hence u ≤ u + u. Thus and satisfy all the conditions of Theorem 2.1 and we apply it to con-clude that the operator equation x + x = x has a solution. Consequently the integral equation and the Equation (1.1) has a solution x∗ defined on J. Furthermore, the sequence {xn}

∞

n=0 of successive approximations defined by (3.5) converges monotonically to x∗. This completes the proof. □

‖y(t)‖ = ‖x(t)‖

=��

T

0

G(t, s)g

�s,max

0≤�≤sx(�)

�ds

��≤�

T

0

G(t, s)��g

�s,max

0≤�≤sx(�)

��ds

≤ K T Mg = r,

‖‖y(t2) − y(t1)‖‖ = ‖‖x(t2) − x(t1)‖‖

=‖‖‖‖‖�

T

0

G(t2, s)g

(s,max

0≤�≤sx(�)

)ds

−�

T

0

G(t1, s)g

(s,max

0≤�≤sx(�)

)ds

‖‖‖‖‖≤�

T

0

||G(t2, s) − G(t1, s)|||||||g

(s,max

0≤�≤sx(�)

)|||||ds

≤ Mg �

T

0

||G(t2, s) − G(t1, s)||ds→ 0 as t1 → t2

(3.18)

⎧⎪⎨⎪⎩

u�(t) ≤ f (t,u(t)) + g

�t,max0≤�≤t

u(�)

�, t ∈ J,

u(0) ≤ u(T).

(3.19)u(t) ≤�

T

0

G(t, s)f̃ (s,u(s))ds +�

T

0

G(t, s)g

(s,max

0≤�≤su(�)

)ds,

Page 10 of 12


Remark 3.2 The conclusion of Theorem 3.1 also remails true if we replace the hypothesis (H4) with the following one.

(H′

4) The HDE (1.1) has an upper solution v ∈ C1(J,ℝ).

Remark 3.3 We note that if the PBVP (1.1) has a lower solution u as well as an upper solution v such that u ≤ v, then under the given conditions of Theorem 3.1 it has corresponding solutions x

∗ and x∗

and these solutions satisfy x∗≤ x∗. Hence they are the minimal and maximal solutions of the PBVP

(1.1) in the vector segment [u, v] of the Banach space E = C1(J,ℝ), where the vector segment [u, v] is a set in C1(J,ℝ) defined by

This is because the order relation ≤ defined by (3.2) is equivalent to the order relation defined by the order cone = {x ∈ C(J,ℝ) ∣ x ≥ �} which is a closed set in C(J,ℝ).

In the following we illustrate our hypotheses and the main abstract result for the validity of conclusion.

Example 3.1 We consider the following HDE

Here f (t, x) = arctan x(t) − x(t) and g(t, x) = tanh x. The functions f and g are continuous on J ×ℝ. Next, we have

for all x, y ∈ ℝ, x > 𝜉 > y. Therefore 𝜆 = 1 >1

𝜉2+1

= 𝜇. Hence the function f satisfies the hypothesis (H1). Moreover, the function f̃ (t, x) = arctan x(t) is bounded on J ×ℝ with bound Mf̃ = 𝜋∕2, so that the hypothesis (H5) is satisfied. The function g is bounded on J ×ℝ by Mg = 1, so (H2) holds. The function g(t, x) is increasing in x for each t ∈ J, so the hypothesis (H3) is satisfied. The HDE (3.20) has a lower

solution u(t) = −2∫

1

0

G(t, s)ds, t ∈ [0, 1], where G(t, s) is a Green’s function associated with the homo-geneous PBVP

given by

Finally, 𝜆K T = supt,s∈J G(t, s) < 1. Thus all the hypotheses of Theorem 3.1 are satisfied and hence the HDE (3.11) has a solution x∗ defined on J and the sequence {xn}

∞

n=0 defined by

[u, v] = {x ∈ C1(J,ℝ) ∣ u ≤ x ≤ v}.

(3.20)

⎧⎪⎨⎪⎩

x�(t) = arctan x(t) − x(t) + tanh�max0≤�≤t x(�)

�, t ∈ J = [0, 1],

x(0) = x(1).

0 ≤ arctan x(t) − arctan y(t) ≤1

�2 + 1(x − y),

(3.21)x�(t) + x(t) = 0, t ∈ J,

x(0) = x(1),

}

G(t, s) =

{es−t+1

e−1, if 0 ≤ s ≤ t ≤ 1,

es−t

e−1, if 0 ≤ t < s ≤ 1.

x0 = −2�

1

0

G(t, s)ds,

xn+1(t) = �

1

0

G(t, s)arctan xn(s)ds

+�

1

0

G(t, s) tanh

(max0≤�≤s

xn(�)

)ds

Page 11 of 12


for each t ∈ J, converges monotonically to x∗.

Remark 3.4 Finally while concluding this paper, we mention that the study of this paper may be extended with appropriate modifications to the nonlinear hybrid differential equation with maxima,

for all t ∈ J = [a, b], where f ,g: J ×ℝ ×ℝ → ℝ are continuous functions. When g ≡ 0, the differential Equation (3.12) reduces to the nonlinear differential equations with maxima,

which is new and could be studied for existence and uniqueness theorem via Picard iterations under strong Lipschitz condition. Therefore, the obtained results for differential Equation (3.12) with maxi-ma via Dhage iteration method will include the existence and approximation results for the differen-tial equation with maxima (3.13) under weak partial Lipschitz condition.

(3.22)

⎧⎪⎨⎪⎩

x�(t) = f

�t, x(t),max

a≤�≤tx(�)

�+ g

�t, x(t),max

a≤�≤tx(�)

�,

x(0) = x(T),

(3.23)

⎧⎪⎨⎪⎩

x�(t) = f

�t, x(t),max

a≤�≤tx(�)

�, t ∈ J,

x(0) = x(T),

AcknowledgementsThe author is thankful to the referee for pointing out some misprints/corrections for the improvement of this paper.

FundingThe author received no direct funding for this research.

Author detailsBapurao C. Dhage1

E-mail: [email protected] Kasubai, Gurukul Colony, Dist. Latur, Ahmedpur 413515,

Maharashtra, India.

Citation informationCite this article as: Approximating solutions of nonlinear periodic boundary value problems with maxima, Bapurao C. Dhage, Cogent Mathematics (2016), 3: 1206699.

ReferencesBainov, D. D., & Hristova, S. (2011). Differential equations with

maxima. New York, NY: Chapman & Hall/CRC Pure and Applied Mathematics.

Dhage, B. C. (2008). Periodic boundary value problems of first order Carathéodory and discontinuous differential equations. Nonlinear Functional Analysis and its Applications, 13, 323–352.

Dhage, B. C. (2010). Quadratic perturbations of periodic boundary value problems of second order ordinary differential equations. Differential Equations & Applications, 2, 465–486.

Dhage, B. C. (2013). Hybrid fixed point theory in partially ordered normed linear spaces and applications to fractional integral equations. Differential Equations & Applications, 5, 155–184.

Dhage, B. C. (2014). Partially condensing mappings in ordered normed linear spaces and applications to functional integral equations. Tamkang Journal of Mathematics, 45, 397–426.

Dhage, B. C. (2015a). Nonlinear D-set-contraction mappings in partially ordered normed linear spaces and applications to functional hybrid integral equations. Malaya Journal of Matematik, 3, 62–85.

Dhage, B. C. (2015b). Operator theoretic techniques in the theory of nonlinear hybrid differential equations. Nonlinear Analysis Forum, 20, 15–31.

Dhage, B. C. (2015c). A new monotone iteration principle in the theory of nonlinear first order integro-differential equations. Nonlinear Studies, 22, 397–417.

Dhage, B. C., & Dhage, S. B. (2014). Approximating solutions of nonlinear first order ordinary differential equations. GJMS Special Issue for Recent Advances in Mathematical Sciences and Applications-13, GJMS, 2, 25–35.

Dhage, B. C., & Dhage, S. B. (2015a). Approximating solutions of nonlinear PBVPs of hybrid differential equations via hybrid fixed point theory. Indian Journal of Mathematics, 57, 103–119.

Dhage, B. C., & Dhage, S. B. (2015b). Approximating positive solutions of PBVPs of nonlinear first order ordinary quadratic differential equations. Applied Mathematics Letters, 46, 133–142.

Dhage, B. C., Dhage, S. B., & Graef, J. R. (2016). Dhage iteration method for initial value problems for nonlinear first order hybrid integrodifferential equations. The Journal of Fixed Point Theory and Applications, 18, 309–326. doi:10.1007/s11784-015-0279-3

Dhage, B. C., & Octrocol, D. (2016). Dhage iteration method for approximating solutions of nonlinear first order ordinary differential equations with maxima. Fixed Point Theory, 17(2).

Heikkilä, S., & Lakshmikantham, V. (1994). Monotone iterative techniques for discontinuous nonlinear differential equations. New York, NY: Marcel Dekker.

Nieto, J. J. (1997). Basic theory for nonresonance impulsive periodic problems of first order. The Journal of Mathematical Analysis and Applications, 205, 423–433.

Nieto, J. J., & Rodriguez-Lopez, R. (2005). Contractive mappings theorems in partially ordered sets and applications to ordinary differential equations. Order, 22, 223–239.

Otrocol, D. (2014). Systems of functional differential equations with maxima, of mixed type. Electronic Journal of Qualitative Theory of Differential Equations, 2014(5), 1–9.

PetruŞel, A., & Rus, I. A. (2006). Fixed point theorems in ordered L-spaces. Proceedings of the American Mathematical Society, 134, 411–418.

Ran, A. C. M., & Reurings, M. C. (2004). A fixed point theorem in partially ordered sets and some applications to matrix equations. Proceedings of the American Mathematical Society, 132, 1435–1443.

Zeidler, E. (1986). Nonlinear functional analysis and its applications, Vol. I: Fixed point theorems. New York, NY: Springer.

mailto:[email protected]

http://dx.doi.org/10.1007/s11784-015-0279-3

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