Positive solutions for 2p-order and 2q-order nonlinear ordinary differential systems

Existence of Three Positive Solutions for a System of Nonlinear Third-order Ordinary Differential Equations

In this work, we use the Leggett-Williams fixed point theorem, we prove the existence of at least three positive solutions of a boundary-value problem for system of third-order ordinary differential equations.

Approximating positive solutions of nonlinear first order ordinary quadratic differential equations

Abstract: In this paper, the authors prove the existence as well as approximations of the positive solutions for an initial value problem of first-order ordinary nonlinear quadratic differential equations. An algorithm for the solutions is developed and it is shown that the sequence of successive approximations converges monotonically to the positive solution of related quadratic differential e...

Positive periodic solutions of singular systems of first order ordinary differential equations

The existence and multiplicity of positive periodic solutions for first non-autonomous singular systems are established with superlinearity or sublinearity assumptions at infinity for an appropriately chosen parameter. The proof of our results is based on the Krasnoselskii fixed point theorem in a cone. 2011 Elsevier Inc. All rights reserved.

Throughout Positive Solutions of Second-order Nonlinear Differential Equations

In this paper, we consider the second-order nonlinear and the nonlinear neutral functional differential equations (a(t)x′(t))′ + f(t, x(g(t))) = 0, t ≥ t0 (a(t)(x(t)− p(t)x(t− τ))′)′ + f(t, x(g(t))) = 0, t ≥ t0 . Using the Banach contraction mapping principle, we obtain the existence of throughout positive solutions for the above equations.

Positive Periodic Solutions of Systems of Second Order Ordinary Differential Equations