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Groups and FieldsHardNormal Subgroups and Quotient Groups

Normal Subgroups and Quotient Groups · Hard problem

In S4S_4, let H=⟨(1 2 3 4),(1 3)⟩H = \langle(1\,2\,3\,4), (1\,3)\rangle, a subgroup of order 88, and let N={e,(1 2)(3 4),(1 3)(2 4),(1 4)(2 3)}N = \{e,(1\,2)(3\,4),(1\,3)(2\,4),(1\,4)(2\,3)\}, the normal subgroup of order 44. It turns out N⊆HN \subseteq H. Using the Second Isomorphism Theorem relation H/(H∩N)≅HN/NH/(H\cap N) \cong HN/N, what is ∣H/(H∩N)∣|H/(H\cap N)|?