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4.4: Reading Questions

  • Page ID
    81053
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    What is the order of the element \(3\) in \(U(20)\text{?}\)

    2

    What is the order of the element \(5\) in \(U(23)\text{?}\)

    3

    Find three generators of \(\mathbb Z_8\text{.}\)

    4

    Find three generators of the \(5^\text{th}\) roots of unity.

    5

    Show how to compute \(15^{40}\pmod{23}\) efficiently by hand. Check your answer with Sage.


    This page titled 4.4: Reading Questions is shared under a GNU Free Documentation License 1.3 license and was authored, remixed, and/or curated by Thomas W. Judson (Abstract Algebra: Theory and Applications) via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.

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