2009 · Q10
Which one of the following is not correct in respect of the sets A and B?
Elementary MathematicsStatistics
- AIf A ⊆ B then B ∪ A = B
- BIf A ⊆ B then B ∩ (A − B) = ∅
- CIf A ⊆ B then B ∩ A = A
- DIf A ∩ B = ∅ then neither A = ∅ nor B = ∅
Explanation
(d) is false: disjoint sets need not both be non-empty.