Let be an abelian group. Prove that is a subgroup of (called the torsion subgroup of ). Give an explicit example where this set is not a subgroup when is non-abelian. A solution: Let . Since the identity is Read More …
Let be an abelian group. Prove that is a subgroup of (called the torsion subgroup of ). Give an explicit example where this set is not a subgroup when is non-abelian. A solution: Let . Since the identity is Read More …