Question

If U = {x : x ∈ N and x < 10}, A = {1, 2, 3, 5, 8} and B = {2, 5, 6, 7, 9}, then n[(A ∪ B)’] is

Options

• 1

• 2

• 4

• 8

Answer 1

1

Explanation;

Hint:

U = {1, 2, 3, 4, 5, 6, 7, 8, 9}

A ∪ B = {1, 2, 3, 5, 8} ∪ {2, 5, 6, 7, 9}

= {1, 2, 3, 5, 6, 7, 8, 9}

(A ∪ B)’ = {1, 2, 3, 4, 5, 6, 7, 8, 9} – {1, 2, 3, 5, 6, 7, 8, 9}

= {4}

n(A ∪ B)’ = 1