A fixed point index approach to Krasnosel’skiĭ-Precup fixed point theorem in cones and applications

We present an alternative approach to the vector version of Krasnosel’skiĭ compression–expansion fixed point theorem due Precup, which is based on index. It allows us obtain new general versions this and also multiplicity results. emphasize that all them are coexistence theorems for operator systems, means every component points obtained non-trivial. Finally, these applied results concerning existence positive solutions systems Hammerstein integral equations radially symmetric (p1,p2)-Laplacian systems.