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Reading Questions 4.4 Reading Questions
1.
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 5th roots of unity.
5.
Show how to compute
\(15^{40}\pmod{23}\) efficiently by hand. Check your answer with Sage.
