问题描述:
已集合A〔a,b,c,d〕集合B〔1,2,3〕,则集合A到集合B的映射有几种?集合B到集合A的映射有几种?
过程详细点```````
择优``````````
过程详细点```````
择优``````````
问题解答:
我来补答展开全文阅读
问题描述:
问题解答:
我来补答