Abstract Algebra/Group Theory/Group/Definition of a Group/Definition of Closure

a*b is in G if a, b are in Group G
Definition of Closure
editLet G be a group with binary operation
Usage
edit- If a, b are in G, a b is in G.
Notice
edit- G has to be a group
- Both a and b have to be elements of G.
- has to be the binary operation of G
- The converse is not necessary true:
- a b is in G does not mean a or b must be in G.