Mathematics for IGCSE & O level - Sets (Section 3 - No. 6)
If the universal set is positive integers less than 5, and A = {prime numbers}, what are the elements of A?
{1, 2, 3, 4}
{2, 3}
{1, 4}
{1, 2, 3}
Erläuterung
Prime numbers less than 5 are 2 and 3.