Exercise 2.8.4 (Orders modulo 7, modulo 11)

Proof.

• The orders modulo $7$ are given in the following array;

  $$\begin{array}{ccccccc}\hfill x\hfill & \hfill 1\hfill & \hfill 2\hfill & \hfill 3\hfill & \hfill 4\hfill & \hfill 5\hfill & \hfill 6\hfill \\ \hfill \text{ order}\hfill & \hfill 1\hfill & \hfill 3\hfill & \hfill 6\hfill & \hfill 3\hfill & \hfill 6\hfill & \hfill 2\hfill \end{array}$$

• Modulo 11:

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