Middle School Definitions
Inverse Operations -- the pair addition and subtraction", or "multiplication and division".
A Set of Numbers form a group of and only being closed by a pair of inverse operations. For example, the set of integers form a group because it is closed under addition and subtraction. We say the set of integers is a group under addition. Note: the set of integers is not a group under multiplication because it is not closed under division.
Inverse Operations -- the pair addition and subtraction", or "multiplication and division".
A Set of Numbers form a group of and only being closed by a pair of inverse operations. For example, the set of integers form a group because it is closed under addition and subtraction. We say the set of integers is a group under addition. Note: the set of integers is not a group under multiplication because it is not closed under division.