【摘 要】
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本期选登试题 (欢迎读者寄来佳答) 16.(56届)设S是一个实数集合,它对于乘法是封闭的(即:若a与b都属于集合S,则ab也属于S).设T,U是S的两个不相交子集,且其并集为S.若T
In th
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本期选登试题 (欢迎读者寄来佳答) 16.(56届)设S是一个实数集合,它对于乘法是封闭的(即:若a与b都属于集合S,则ab也属于S).设T,U是S的两个不相交子集,且其并集为S.若T
In this issue, select the test questions (welcome readers to send a good answer) 16. (56) Let S be a set of real numbers, which is closed for multiplication (ie: if a and b belong to set S, then ab also belongs to S) Let T, U be two disjoint subsets of S, and its union is S. If T
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