(adsbygoogle = window.adsbygoogle || []).push({}); Mathmatical proofs help please!!

1. Must two uncountable sets have the same cardinality?

a countable union of countable sets is countable.

Is a finite set necessarily countable?

If the union of A and B is infinite, then A or B must be inifinte

2. Just use definitions of Uncountable, Countable, finite, and infinite, and cardinality to do these proofs.

3. I know what the answers are just by thinking but I cannot prove the answers please help or I will fail

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# Homework Help: Mathmatical proofs help please

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