Positive Solutions For Higher Order Ordinary Differential Equation's Boundary Value Problems

In this paper,We are concerned with positive solutions of higher order ordinary differential equation's boundary value problem,here f(x,u) satisfies suplinear conditions or sublinear conditions with respect to u.When m 0, existing results of positive solutions have been obtained by Paul.W.Eloe and Johnny Henderson in 1997[1] and 1995[2].In this paper, we permit m = 0 . Obviously m2 + /(x,w) don't satisfy suplinear conditions or sublinear conditions with respect to u.There is a little of difference between [l]and [2] in the method of prov-ing.In solving (l),we use different methods with [1], The authors didn't obtain the Green's functions in [l],they estimated the properties of the Green's functions directly ,but in this paper,we calculated firstly the Green's functions , Then estimated the properties using the Green's functions; we use the similar method with [2] in solving (2). To obtain the results,we turn it from high dimension to low dimension in solving (2).