Let A= {1, 2, {3, 4}, 5}. Which of the following statements are incorrect and why? (i) Φ ∈ A (ii) Φ ⊂ A

Solution:

Provided that A= {1, 2, {3, 4}, 5}

(i) Φ ∈ A is incorrect

Φ is not an element of A.

(ii) Φ ⊂ A is correct

Φ is a subset of every set.