摘要
We prove the following main result: Let X be a normed linear space,fn ∈ X*\{θ},Hn = {x ∈ X: fn(x) = l},n = 0, 1,2,...Then w* - limfn = f0 iff H0 lim inf Hn and θ limsup Hn; when X is a reflexive Banach space, lim ||fn - f0|| = 0. If and only if θ w-limsup Hn Ho It simplifies the related results in [1].
在本文中,我们证明下述主要结果:(i)设X是赋范线性空间,fn∈X*\{θ}Hn{x∈X:fn(x)=1},n=0,1,2,…,则w*-limfn=fo当且仅当Ho liminf Hn且θ limsupHn;(ii)当X是自反的Banach空间时,lim||fn-fo||=0当且仅当θ w-limsup Hn H0.