Question

1. If n (A × B) = 10 then the number of non empty proper subsets of A × B is

1) 2^10 2) 2^10 – 1 3) 2^10+ 1 4) 2^10– 2​

Answer 1

Number of proper subsets = 2^n - 1

Here ,n = 10

so, 2^10 - 1 = 1024 - 1 = 1023

For non-empty proper subsets ( exclude phi ) = 2^10 - 1 - 1 = 2^10– 2

Correct option is 4). 2^10– 2