When A∈B(H), B∈B(H) and C∈B(H ) are given, we denote by M(D,E,F) an operator, acting on the Hilbert space HHH , of the f设A∈B(H),B∈B(H),C∈B(H )为给定的三个算子,用M(D,E,F)= 表示一个作用在H(?) H(?)