For Zn = { 0, 1 ,...,n-1}, the algebraic structure (Zn, +, . ) is a "ring", i.e., it has nearly all of the usual properties of addition and multiplication that we use unconsciously most of the time(where the opertaions are defined by performing them in Z and then recording the remainder on division by n). In Z, of course, the only invertible elements with respect to multiplication (a for which there is some b such that ab = 1), are +-1. PRove that the invertible elements with respect to multiplication in Zn are exactly those elements a such that a and n are relatively priime; that is , gcd{a,n}=1(adsbygoogle = window.adsbygoogle || []).push({});

can some one give me a hint on wat to do in this problem? i woud really apriciate it!!

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# Homework Help: Algebraic structure

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