Recent content by hari!

I'm a little ashamed to say this, but I was reading |a| as absolute value of a, not order of a. This makes perfect sense then, thank you both for your help!

I'm not sure I follow; the problem states that |a| divides k, not that k is the order of any element in the subgroup. So how do we know that ak = e for any a in H?

Homework Statement Let G be an abelian group, k a fixed positive integer, and H = {a is an element of G; |a| divides k}. Prove that H is a subgroup of G. Homework Equations Definition of groups, subgroups, and general knowledge of division algorithm. The Attempt at a Solution I...