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Exercise 14.4.1
Prove that is solvable, and compute its order.
Answers
Proof. Recall that , where and are cyclic, thus solvable, hence is solvable by Theorem 8.1.4.
By Exercise 14.3.3(a), has index 2 in , therefore is a normal subgroup of , and
The group is cyclic, of prime order , therefore is solvable, and is solvable. The same Theorem 8.1.4 shows that is solvable.
By Exercise 14.3.26,
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