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I'm having trouble figuring out

Find the order of the element $\overline{8} + \langle\overline{6} \rangle$ in the quotient group $\mathbb{Z}_{60} / \langle \overline{6} \rangle$

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    One way would be to just add $8$ to itself and see what happens. Have you done this?2011-12-07

1 Answers 1

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The elements of $\mathbb{Z}_{60}/\langle \overline{6}\rangle$ are $\langle \overline{6}\rangle$, $\overline{1}+\langle \overline{6}\rangle$, $\overline{2}+\langle \overline{6}\rangle$, $\overline{3}+\langle \overline{6}\rangle$, $\overline{4}+\langle \overline{6}\rangle$, and $\overline{5}+\langle \overline{6}\rangle$. which if these is equal to $\overline{8}+\langle \overline{6}\rangle$? How many times do you have to add that one to itself to get $\langle \overline{6}\rangle$?

There’s no law against doing some actual computations to see what’s going on!

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    @pigishpig: No, the answer is $3$. $\overline{8}+\langle\overline{6}\rangle=\overline{2}+\langle\overline{6}\rangle$; $\left(\overline{2}+\langle\overline{6}\rangle\right)+\left(\overline{2}+\langle \overline{6} \rangle\right)=\overline{4}+\langle\overline{6}\rangle$; and $\left(\overline{4}+\langle\overline{6}\rangle\right)+\left(\overline{2}+\langle \overline{6} \rangle\right)=\langle \overline{6} \rangle$.2011-12-07