Let A and B be finite sets. Prove the following: (a) |A∪B|=|A|+|B|−|A∩B| (b) |A × B|...

Let A and B be finite sets. Prove the following:

(a) |A∪B|=|A|+|B|−|A∩B|

(b) |A × B| = |A||B|

(c) |{f : A → B}| = |B||A|

Expert Solution

Colby Messinger answered 2 years ago

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