Question

State which of the following sets are empty and which are not?
Set of odd natural numbers divisible by $2$

Answer 1

Solution:- Empty

Empty set $\left(\varphi \right)$: which has no elements.

Natural numbers $=1,2,3,4,5,.........$

Odd natural numbers $=1,3,5,.........$

No odd number is divisible by 2.

Therefore, no element in this set.

Hence, the set of odd natural numbers divisible by 2 is empty.