AATA Reading Questions

Reading Questions 4.4 Reading Questions

What is the order of the element $3$ in $U (20) ?$

What is the order of the element $5$ in $U (23) ?$

Find three generators of $Z_{8} .$

Find three generators of the $5^{th}$ roots of unity.

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