Exact number of positive solutions for a class of semipositone problems ✩

This paper is concerned with the boundary value problems y + λ(yp − yq ) = 0 and y(−1) = y(1) = 0, where p >q >−1 and λ>0 is a positive parameter. We discuss the existence of positive solutions and give a complete study.  2003 Elsevier Science (USA). All rights reserved.