Let (G,+) be a group. A nonempty subset H of G is a subgroup of G if and only if for all a, b ∈ H, the element?
Let (G,+) be a group. A nonempty subset H of G is a subgroup of G if and only if for all a, b ∈ H, the element?
Explanation
- The correct answer is: a + (-b) ∈ H.
- A nonempty subset H of G is a subgroup of G if and only if it is closed under the group operation + and contains the inverse of each of its elements.