Existence, nonexistence and multiplicity of positive solutions for nonlinear fractional differential equations

Abstract

In this paper, we consider the existence, nonexistence and multiplicity of positive solutions for nonlinear fractional differential equation boundary-value problem $$\left\{ \begin{array}{@{}l}-D^{\alpha}_{0+}u(t)=f(t,u(t)), \quad t\in[0,1]\\[3pt]u(0)=u(1)=u''(0)=0\end{array} \right.$$ where 2<α≤3 is a real number, and \(D^{\alpha}_{0+}\) is the Caputo’s fractional derivative, and f:[0,1]×[0,+∞)→[0,+∞) is continuous. By means of a fixed-point theorem on cones, some existence, nonexistence and multiplicity of positive solutions are obtained.