In this paper ,it is proved that if X is a URED Banach space and M is a closed and proximinal subspace of X,then the quotient space X/M is also URED.
证明了若X是URED的Banach空间且M是X的任意可逼近闭子空间 ,则商空间X/M也是URED的Banach空间 。
In this paper,It Is shownthat three types Banachspace there are proximinal sets which lacks property(β).
说明了三种类型的Banach空间都存在不具有(β)性质的可逼近集,指出在等价范数的意义下,每个具基的Banach空间都存在不具有(β)性质的可逼近集。