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

Let S be the set of all real numbers except -1.

Define * on S by:

a * b = a + b + ab

2. Relevant equations

i) find 3 * 5

ii) find -2 * 6

iii) show that S with the operation * is a group

iv) find a solution of the quation 2 * x * 3 = 7 in S

3. The attempt at a solution

Ok, I have no clue on these. Here is what I've attempted:

i) 28

ii) -8

iii) ???

iv) ???

Could someone give me a hand? :)

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# Sets and groups

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