Properties Of Difference Of Sets –
(1) If A ⊂ B, then A – B = ϕ and B – A ≠ ϕ
(2) If A = ϕ, then A – B = ϕ, and B – A = B
(3) If, A ∩ B = ϕ, then A – B = A and B – A = B
(4) If, A = B, then A – B and B – A are both null set
(5) Set A – B is a subset of A, i.e., A – B ⊆ A
(6) The sets A – B, A ∩ B and B – A are mutually disjoint
(7) A – B = (A ∪ B) – B = A – A ∩ B
(8) A – B ≠ B – A
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