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什麼是可数无穷
更新时间: 2020-09-23 00:00:00  

可数无穷是指,集合中的元素可以与自然数相对应,也就是说可以用自然数来“数”它的数量,从而其数量为可数无穷。比如说:整数的全体可以和自然数相对应;偶数的全体可以和自然数相对应;奇数的全体可以和自然数相对应;同样,有理数也可以和自然数相对应。

关键词: 可数 无穷

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