Q. 4 If U = {1, 2, 3, 4, 5, 6, 7, 8, 9 }, A = {2, 4, 6, 8} and B = { 2, 3, 5, 7}. Verify that
(i) (A B)′ = A′ B′
(ii) (A B)′ = A′ B′
U = {1, 2, 3, 4, 5, 6, 7, 8, 9 }, A = {2, 4, 6, 8} and B = { 2, 3, 5, 7}
(i) (A B)′ = A′ B′
L.H.S = (A B)′ = U - (A B) = {1,9}
R.H.S = A′ B′ = {1,3,5,7,9} {1,4,6,8,9} = {1,9}
L.H.S = R.H.S
Hence,the statement is true.
(ii) (A B)′ = A′ B′
L.H.S = U - (A B) ={1,3,4,5,6,7,8,9}
R.H.S = A′ B′ = {1,3,5,7,9} {1,4,6,8,9} = {1,3,4,5,6,7,8,9}
L.H.S = R.H.S
Hence,the statement is true.