Z is the set of integers. ⟨Z, *⟩ forms a group if * is:
Pick an option to check yourself, or open the answer below.
Show answer & explanation
Correct answer: A. a * b = a + b + 2
Explanation
a * b = a + b + 2 is closed and associative, has identity −2 (a + (−2) + 2 = a) and inverse −a − 4. The others fail associativity or closure.More Discrete Structures and Optimisation questions
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