In the questions below: G is a finite group; H≤G a subgroup of G;∣G:H∣ the index of H in G;∣X∣ the number of elements of X⊆G;Z(G) the center of G;G′ the commutator subgroup of G;NG(H) the normalizer of H in G;CG(H) the centralizer of H in G; and Sn the n-th symmetric group.
Assume ∣G′∣=2. Prove that ∣G:G′∣ is even. group theoryabstract algebrasuperior algebrasuperior algebra unsolved