that is not true, the cardinal of [0, N] and [0, 2N] are exactly the same.
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送交者: steven 于 2008-12-12, 01:55:47:
回答: 无穷大和无穷大之间还是有区别的 由 supernova 于 2008-12-12, 01:43:34:
The cardinality of two infinite sets are equal if there is an one-to-one mapping between elements of two sets. Hence [0, n] and [0, 2n] are equal.
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