(a,b)*(c,d)=(ac,bc+d)on the set {(x,y)∈ℝ*ℝ:x≠0}(adsbygoogle = window.adsbygoogle || []).push({});

1.(b,a)*(d,c)=(bd,ad+c) so not commutative

2.[(a,b)*(c,d)]*(e,f)=(ace,(bc+d)e+f)=(ace,bce+de+f)

(a,b)*[(c,d)*(e,f)]=(ace,bce+de+f) so associative

Is that correct so far? What do I do next?

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# Am I verifying that this is a group correctly?

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