Suppose A and B are countable. Explain why P(s), power set, and f: A ->B are not necessarily countable.(adsbygoogle = window.adsbygoogle || []).push({});

P(s) is only countable if A and B are finite, am I am correct? Otherwise, the power set of an infinite set is not countable. As for f: A -> B, doesn't f have to be a bijection?

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# Homework Help: A, B are countable. P(s), power set, and f: A-> not always countable?

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