U = {1, 2, 3, 4, 5, 6, 7}, A = {1, 2, 5}, B = {2, 4, 6}, C = {3, 4, 5, 6, 7} হলে (B ∩ C)′ =?

প্রশ্ন: U = {1, 2, 3, 4, 5, 6, 7}, A = {1, 2, 5}, B = {2, 4, 6}, C = {3, 4, 5, 6, 7} হলে (B ∩ C)′ =?

সমাধান:
B ∩ C = {2, 4, 6} ∩ {3, 4, 5, 6, 7}
= {4, 6}

∴ (B ∩ C)′ = U − (B ∩ C)
= {1, 2, 3, 4, 5, 6, 7} − {4, 6}
= {1, 2, 3, 5, 7}