Intersection of Product spaces

[math8]

Give an example where
(A1 intersect A2)X(B1 intersect B2) is strictly contained in (A1XB1)intersect (A2XB2).

For the union instead of the intersection I can see the reverse strict containment easily just by drawing. But for the intersection for some reason, I cannot see when the containment can be strict.

 

[tiny-tim]

Hi math8!

I think you're right … I think they're the same.