Operation on Se...

If P ⋂ Q = Q and P ⋂ Q = P then which among the following cannot be true?

If M' = N, then (M ⋂ N)′ is ____

If P = Q′, then (P ⋃ Q)′ is ____

If A = {a, b, e, g, k, I, m, n}, B = {c, d, s, t, v,} and ⋃ is the set of all the letters of English alphabet, the A′ ⋃((A ⋂ B) ⋃ B′) is equal to ____

Which one among the following is incorrect?

For any two non empty sets P and Q, if P − Q = P and Q − P = Q, then ______

If n(P) = 18 - x, n (Q) = 24 + x and n (P ⋃ Q) = 34, then n(PΔQ) = _____

If P = {a, b, c, d} and Q = {a, c, e} then PΔQ =?

If P and Q are two non-empty sets and P - Q is a null set, then ____