Multiple positive solutions to a third-order discrete focal boundary value problem

Three Positive Solutions to a Discrete Focal Boundary Value Problem

We are concerned with the discrete focal boundary value problem ∆3x(t−k) = f(x(t)), x(a) = ∆x(t2) = ∆2x(b+ 1) = 0. Under various assumptions on f and the integers a, t2, and b we prove the existence of three positive solutions of this boundary value problem. To prove our results we use fixed point theorems concerning cones in a Banach space.

Positive Solutions to a Second-Order Discrete Boundary Value Problem

Multiple Positive Solutions to a Fourth-order Boundary-value Problem

We study the existence, localization and multiplicity of positive solutions for a nonlinear fourth-order two-point boundary value problem. The approach is based on critical point theorems in conical shells, Krasnosel’skĭı’s compression-expansion theorem, and unilateral Harnack type inequalities.

Positive Solutions for a Singular Third Order Boundary Value Problem

The existence of positive solutions is shown for the third order boundary value problem, u′′′ = f (x,u),0 < x < 1, u(0) = u(1) = u′′(1) = 0, where f (x,y) is singular at x = 0 , x = 1 , y = 0 , and may be singular at y = ∞. The method involves application of a fixed point theorem for operators that are decreasing with respect to a cone. Mathematics subject classification (2010): 34B16, 34B18.

Computing the positive solutions of the discrete third-order three-point right focal boundary-value problems

we are concerned with the discrete right-focal boundary value problem A3z(t) = f(t, z(t + l)), z(ti) = Az(tz) = A2z(ts) = 0, and the eigenvalue problem A3z(t) = Xa(t)f(z(t + 1)) with the same boundary conditions, where tl < t2 < t3. Under various assumptions on f, a, and X, we prove the existence of positive solutions of both problems by applying a fixed-point theorem. @ 2003 Elsevier Science L...