A=B,they are not two sets...No definion,no right
A=B,they are semantically not two sets, but symbolically two set
A和B指同一个集合,如果A=B;A和B指不同集合,如果A!=B。但A和B是不同符号。
jinjing
2010-07-24 11:06:23A=B,they are not two sets...No definion,no right