A subset \(S\) of a group \(G\) is called subgroup if it is a subgroup.
The subset \(S\) is a subgroup if and only if it is closed under multiplication and it contains the inverse of each of its elements.
A subset \(S\) of a group \(G\) is called subgroup if it is a subgroup.
The subset \(S\) is a subgroup if and only if it is closed under multiplication and it contains the inverse of each of its elements.