Mathematics for IGCSE & O level - Sets (Section 3 - No. 19)
If set A = {1, 2, 3} and set B = {4, 5, 6}, which statement is true?
A ∩ B = {1, 2, 3, 4, 5, 6}
A ∩ B = {}
A ∪ B = { }
A ⊆ B
Explicaţie
Since A and B have no common elements, their intersection is an empty set.