Let A = {1, 2, 4, 5} B = {2, 3, 5, 6} C = {4, 5, 6, 7}. Verify the following identities:

A– (B C) = (A – B) (A – C)

(B C) = {x:x ϵ B and x ϵ C}


= {5, 6}


(A – (B C)) =


A–(B C) is defined as {x ϵ A : x (B C)}


A = {1, 2, 4, 5}


(B C) = {5, 6}


(A – (B C)) = {1, 2, 4}


R.H.S:


(A – B) =


A–B is defined as {x ϵ A : x B}


A = {1, 2, 4, 5}


B = {2, 3, 5, 6}


A–B = {1, 4}


(A–C) =


A–C is defined as {x ϵ A : x C}


A = {1, 2, 4, 5}


C = {4, 5, 6, 7}


A–C = {1, 2}


(A – B) (A–C) = {x:x ϵ (A – B) OR x ϵ (A – C) }.


= {1, 2, 4}


Hence verified.


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