Question

Find the set A ∩ B. U={1, 2, 3, 4, 5, 6, 7, 8, 9, 10} A={1, 2, 3, 4} B={1, 2, 7}

Answer 1

A intersect B is just the elements of the set that both sets have in common
so A∩B={1,2}