I'm having a brain cramp, lol.
Doing some practice problems for a Final, and am showing groups are isomorphic.
I'm trying to show integers with addition are isomorphic with

I'm good on everything except showing a surjection, could I get a quick refresher?

just check if it's one-to-one and onto

That's exactly what i'm asking about. I'm good on showing the injection (1-1), I'm stuck on the surjection (onto)

here maybe this link will help you out

http://math.stackexchange.com/questions/26371/is-a-linear-tranformation-onto-or-one-to-one

Well, you probably already noticed that [[ 1 m ] [ 0 1 ]] x [[ 1 n ] [ 0 1 ]] = [[ 1 m+n ] [ 0 1 ]]

Now the bijection ( = injection and surjection) is quiete obvious :

(Z,+) ----> (G,x)
n ----> [[ 1 n ][ 0 1 ]]

since, to each element of G, corresponds 1 and 1 only integer n.

Thank you, that makes sense and makes me feel like my brain is fried right now.
I think I need some sleep, lol.