Question

If X and Y are two sets and X′ denotes the complement of X, then X ∩ (X ∪ Y)′ is equal to
(A) X (B) Y (C) φ (D) X ∩ Y

Answer 1

Let

X={1,2,3}

 Y={1,2,3,4}

and U={1,2,3,4,5}

X ∩ (X ∪ Y)′ is equal to X ∩ U-{1,2,3,4}--->  X ∩ {5}---> φ

THEREFORE THE OPTION IS (C) φ