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{A1,A2,A3.An}是集合A的划分,证明{A1交B,A2交B.An交B}是集合A交B的划分.离散

题目详情
{A1,A2,A3.An}是集合A的划分,证明{A1交B,A2交B.An交B}是集合A交B的划分.
离散
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答案和解析
A = A1UA2U...UAn ( Ai∩Aj =Φ, i ≠j )
AUB =(A1UA2U...UAn)UB
=(A1UB)U(A2UB)U.U(AnUB) ( (AiUB)∩(AjUB) =Φ, i ≠j )
=>
{A1UB,A2UB,...,AnUB}是集合AUB的划分