POSlTlVE SOLUTl0NS 0F A FOURTH 0RDER BOUNDARY VALUE PROBLEM

摘要

The existence of positive solutions of the nonlinear fourth order problem u(4)(x)=λα（x)f(u(x)),u(0)=u′（0)=u′（1)=um(1)=0 is studied,where a:[0,1]→R may change sign,f(0)>0,λ>0 is sufficiently small.Our approach is based on the Leray-Schauder fixed point theorem.