For any two sets A and B, prove that A – (A – B) = A ∩ B
A – (A – B) = A ∩ B
Let us consider LHS A – (A – B)
Let, x ∈ A – (A–B) = x ∈ A and x ∉ (A–B)
x ∈ A and x ∉ (A ∩ B)
= x ∈ A ∩ (A ∩ B)
= x ∈ (A ∩ B)
= (A ∩ B)
= RHS
Hence proved.
If A = {x : x ϵ R, x < 5} and B = {x : x ϵ R, x > 4}, find A ∩ B.
Prove that A – B = A ∩ B.’
Find the symmetric difference A Δ B, when A = {1, 2, 3} and B = {3, 4, 5}.
Prove that A ∩ (A ⋃ B)’ = ϕ
If A = {3, {2}}, find P(A).