



 
Sean, Suppose some element p is in both sets a and b then (p,p) is in both a x b and b x a. If p is the only element is both a and b then (p,p) is the only element in both a x b and b x a. Suppose there are two different elements p and q in both a and b. Suppose there are more than two different elements in both a and b. Harley  


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