NEW MULTIPLE FIXED POINT THEOREMS FOR SUM OF TWO OPERATORS AND APPLICATION TO A SINGULAR GENERALIZED STURM-LIOUVILLE MULTIPOINT BVP
L. Bouchal, K. Mebarki
Abstract
In this paper, we develop some new multiple fixed point theorems for the sum of two operators $T+S$ where $I-T$ is Lipschitz invertible and $S$ is a $k$-set contraction on translate of a cone in a Banach space.
New existence criteria for multiple positive solutions of a singular generalized Sturm-Liouville multipoint boundary value problem are established. The article ends with an illustrative example.
Keywords: Fixed point; sum of operators; cone; Sturm-Liouville BVP; multiple positive solutions.