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Groups and FieldsEasyNormal Subgroups and Quotient Groups

Normal Subgroups and Quotient Groups · Easy problem

In Z36\mathbb Z_{36}, let H=⟨4⟩H = \langle 4\rangle and N=⟨9⟩N = \langle 9\rangle. The Second Isomorphism Theorem needs H∩NH \cap N. What is ∣H∩N∣|H \cap N|?