Trying to brush up on my group theory before next year...

One thing I've always had trouble with is proving two groups are (or in this case aren't) isomorphic.

So here's my Q.

Show that and are not isomorphic.

My thoughts... I'm thinking something along the lines of, an element of order 6 in the group is just the identity element since if you have then ? Whereas an element of order 6 in the group is not.

Think this is wrong so any help appreciated.