Using the definition of the binary product

1. Dec 1, 2008

mbcsantin

Prove or find counterexamples:
If A x B = empty set then A = empty set or B = empty set.

2. Dec 2, 2008

HallsofIvy

Well, you titled this "using the definition of the binary product"?
So what is the definition of A x B?

Then consider using an indirect proof: If neither A nor B is empty...