SOLUTION: Let H={2^k:k∈Z}. Show that H is a subgroup of Q^*.

Question 1184602: Let H={2^k:k∈Z}. Show that H is a subgroup of Q^*.
Answer by ikleyn(52905)   (Show Source): You can put this solution on YOUR website!
.

You should check or prove that

        - (1)   the product of any two elements of H does belong to H;

        - (2)   the unit element does belong to H;

        - (3)   the inverse element to any element of H does belong to H.

All three statements/steps are OBVIOUS.

I want to say that their proofs are obvious for every statement.

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