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 is defined as {x ϵ B : x C}


B = {2, 3, 5, 6}


C = {4, 5, 6, 7}


B–C = {2, 3}


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


= {2}


R.H.S:


(A B) = {x:x ϵ A and x ϵ B}


= {2, 5}


(A C) = {x:x ϵ A and x ϵ C}


= {4, 5}


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


= {2}.


Hence Verified.


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