Nondegeneracy of positive solutions to homogeneous second-order differential systems and its applications

This article considers the Dirichlet problem of homogeneous and inhomoge-neous second-order ordinary differential systems. A nondegeneracy result is proven for positive solutions of homogeneous systems. Sufficient and necessary conditions for the existence of multiple positive solutions for inhomogeneous systems are obtained by making use of the nondegeneracy and uniqueness results of homogeneous systems.