I want to prove Cauchy's Lemma for abelian groups:
If $G$ is abelian and there exists a prime such that $p$ divides the order of $G$, then there exists a $g \in G$ such that $p=\mathrm{ord}(g)$
I am looking for some tips to prove this (so please no full solutions).
I know that if $G$ is abelian it holds that: $Z(G)=G$ and I know that every subgroup of G is normal in $$G.
Maybe I should consider $U:=\langle g\rangle\subset G$ for some $g \in G$. The order of $U$ should divide the order of $G$, which should be something like $p^rm?$ (Because p divides it)
From now I don't know how to continue (If the way is good so far).
Maybe I should use Sylow's theorem?
Any help is appreciated :)
Hints: