摘要
本文最初欲把Belman不等式推广成:已知φ(x)≤C(x)+K1(x)∫xaH1(ζ)φ(ζ)dζ+K2(x)∫xaH2(ζ)φ(ζ)dζ(其中:Ki(x)≥0,Hi(x)≥0,i=1,2),求适合上述不等式的φ(x)的最优上界Ψ(x)(x≥a)。但后来证明这个最优上界Ψ(x)是不能用初等方法求出的,只知道Ψ(x)是存在的且适合积分方程:Ψ(x)=C(x)+K1(x)∫xaH1(ζ)Ψ(ζ)dζ+K2(x)∫xaH2(ζ)Ψ(ζ)dζ。
The main conclusion of the paper is as fallows: Theorem: suppose x=(x 1,x 2,…,x m),ξ=(ξ 1,ξ 2,…,ξ m) are points of m-dimension euclidean space E m,A(x,ξ) =(a ij ) p×p ≥0, here a ij =a ij (x,ξ) (i,j= 1,P ──,α≤ξ≤x≤β). Let φ(x)=(φ 1(x),φ 2(x),φ p(x)) τ. Ψ(x)=(Ψ 1(x),Ψ 2(x),Ψ p(x)) τ. C(x)=(C 1(x),C 2(x),…,C p(x)) τ,if φ(x)≤C(x)+∫ x αA(x,ξ)φ(ξ)dξ, then we have φ(x)≤Ψ(x) (α≤x≤β). Here Ψ(x) is only solution of the integral equation Ψ(x)=C(x)+∫ x αA(x,ξ)Ψ(ξ)dξ. Besides, the relevant conclusion of the above integral inequality is also valid when the “≤'is changed into “<,≥,>”。
出处
《安徽大学学报(自然科学版)》
CAS
1997年第2期12-16,共5页
Journal of Anhui University(Natural Science Edition)