Question

Set of natural numbers A = $A=\{x:xϵN\}$ is a proper subset of which of the following

• A. Set of whole numbers $A_1=\{x:xϵW\}$
• B. Set of Real numbers $A_2=\{x:xϵR\}$
• C. Set of Integers $A_3=\{x:xϵI\}$
• D. All of the above.

Answer 1

The correct option is D All of the above.

A set A is said to be a proper subset of B if A is a subset of B and A $\ne$ B i.e if
(i) Every element of A is an element of B
(ii) B has atleast one element which is not an element of A.