Question

Let U = {1, 2, 3, 4, 5, 6}, A = {1,4} and B = {2,3,5}. Find A’∩B’.

(a) {2,3,5,6}

(b) {1,2,3}

(c) {6}

(d) {1,2,3,4,5,6}

I have been asked this question in final exam.

The question is from Complement of a Set topic in section Sets of Mathematics – Class 11

Answer 1

The correct choice is (c) {6}

For explanation: Complement of a set A is a set which contains elements of U which are not the elements of A. A’ = U-A = {1, 2, 3, 4, 5, 6} – {1,4} = {2,3,5,6} and B’ = U-B = {1, 2, 3, 4, 5, 6} – {2,3,5} = {1,4,6}. A’∩B’={2,3,5,6} ∩ {1,4,6} = {6}.