# How to find the value of U(n) on abstract algebra Example U(8) = {1,3,5,7}

Question
Abstract algebra
How to find the value of U(n) on abstract algebra
Example U(8) = {1,3,5,7}

2020-11-30
By the definition ,
$$\displaystyle{U}{\left({n}\right)}={\left\lbrace{a}:{a}{<}{n}{\quad\text{and}\quad}{\gcd{{\left({a},{n}\right)}}}={1}\right\rbrace}$$</span>
Hence to U(n) is the collection of all positive integers m less than such that m is coprime to n.

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