If S1 and S2 are finite sets, show that |S1 x S2| = |S1||S2|.(adsbygoogle = window.adsbygoogle || []).push({});

Here is what I've tried:

Let |S1| = m and |S2| = n.

Let P(k) be true. That is, P(k) = |S1 x S2| = km.

P(1) is true since, if |S1| = 1 and |S2| = 1, |S1 x S2| = 1.

Now, let |S1| = k+1 and |S2| = m. Then, P(k+1) = |S1 x S2| = (k+1)m ??

This is as far as I have gotten.

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# Prove by Induction (Cardinality)

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