Question

what is subset? what is it's notation.​

Answer 1

$\huge\mathfrak\red{❆AɴSᴡᴇR❆}$

A subset is a set whose elements are all members of another set. The symbol "⊆" means "is a subset of". The symbol "⊂" means "is a proper subset of". Since all of the members of set A are members of set D, A is a subset of D.

Answer 2

Answer:

A subset is a set whose elements are all members of another set. The symbol "⊆" means "is a subset of". The symbol "⊂" means "is a proper subset of". Since all of the members of set A are members of set B, A is a subset of B.