Hi.

I need to prove or disprove the following:

1. Let and . A is a Group.

2. Let and . A is a Group.

both with the operation:

My intuition says 1 is true and 2 is false (the unit element in 1 is , and with simple algebra I can find the inverse element for a given element ), but I'm not sure about 2.

Can someone please give me some help with it?

Thanks in advanced!