At first glance these things seem so intuitive and familiar from other maths (like distribution) that I don't see how/where to start in proving them; while I know its probably quite simple. I understand what union and intersection are, but I'm unsure if multiplying two sets means a new set with elements being every permutation between the two sets.(adsbygoogle = window.adsbygoogle || []).push({});

Trichotomy - [tex]A \subseteq B , B \subseteq C then A \subseteq C[/tex]

For non empty sets, [tex]A \times (B \cap C) = (A \times B) \cap (A \times C)[/tex]

[tex](A \times B) \cap (A\timesB) = (A \cap B) \times (A \cap B)[/tex]

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# Basic set theory proofs

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