ON THE EXISTENCE OF POSITIVE SOLUTIONS FOR BVPS OF NONLINEAR SINGULAR FOURTH-ORDER DIFFERENTIAL EQUATIONS

Abstract

In this paper, by means of the fixed point theorems of the cone expansion andcompression of norm type, an explicit interval for λ is derived such that for any λ in thisinterval, the existence of at least one positive solution to singular boundary value problemin question. Our results extend and improve many known results in the field including bothsingular and non-singular cases.