I'm taking my first abstract algebra course and I understand the formal definition of a group:
- Closure: $\forall a, b \in G, a \cdot b \in G$
- Associativity: $(a \cdot b) \cdot c = a \cdot (b \cdot c)$
- Identity: $\exists e \in G$ such that $e \cdot a = a \cdot e = a$
- Inverse: $\forall a \in G, \exists a^{-1} \in G$ such that $a \cdot a^{-1} = a^{-1} \cdot a = e$