How Can Set Identities Help with Cartesian Product Homework?

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Set identities do not directly apply to Cartesian products, leading to the conclusion that traditional methods are more effective for this homework problem. The discussion illustrates that if (a, d) belongs to A X (B ∪ C), then a must be in A, and d must be in either B or C, which implies (a, d) is in (A X B) or (A X C). This establishes that A X (B ∪ C) is a subset of (A X B) ∪ (A X C). The reverse subset proof follows a similar logic. Ultimately, while set identities are not applicable, the problem can still be solved using established subset proofs.
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Homework Statement



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Homework Equations



I have to use these set identities:

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The Attempt at a Solution



Pretty sure this is impossible because there's no identity for the Cartesian product.
 
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Just go at it the old fashion way.

Suppose (a, d) \in A X (B \cup C). Then a \in A. Also d \in B or d \in C. So (a,d) \in (A X B) or (a,d) \in (A X C).

Thus (a,d) \in (A X B) \cup (A X C).

Therefore A X (B \cup C) \subseteq (A X B) \cup (A X C).

Proving the subset goes the other way follows similarly.
 
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