Let A = {1, 2, 3, 4}, B = {1, 2, 3} and C = {2, 4}. Find all sets X such that: \[\] X $ \subseteq $ B and X $ \subseteq $ C

Answer 1

Given, A = {1, 2, 3, 4}, B = {1, 2, 3} and C = {2, 4}.

Subsets of B are: $ \phi $, {1}, {2}, {3}, {1, 2}, {1, 3}, {2, 3}, {1, 2, 3}.

Subsets of C are: $ \phi $, {2}, {4}, {2, 4}

Since X is a subset of both B and C, therefore, X = $ \phi $, {2}.