(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Show that (S, *) is a group where S is the set of all real numbers except for -1. Define * on S by a*b=a+b+ab

3. The attempt at a solution

Well I know that i have to follow the axioms to prove this. So I started with G1 which is associativity. This one I got to work. Then G2 says i need to find an identity element. But this is where i got confused. I think that the identity element is 0. but i don't know if that is write. I don't really know how to find it. Then finally G3 is the inverse and I also got stuck here. I don't really know what the inverse would be. Can any one help.

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# Homework Help: Identity element for group theory

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