How Can Set Identities Help with Cartesian Product Homework?

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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) [itex]\in[/itex] A X (B [itex]\cup[/itex] C). Then a [itex]\in[/itex] A. Also d [itex]\in[/itex] B or d [itex]\in[/itex] C. So (a,d) [itex]\in[/itex] (A X B) or (a,d) [itex]\in[/itex] (A X C).

Thus (a,d) [itex]\in[/itex] (A X B) [itex]\cup[/itex] (A X C).

Therefore A X (B [itex]\cup[/itex] C) [itex]\subseteq[/itex] (A X B) [itex]\cup[/itex] (A X C).

Proving the subset goes the other way follows similarly.