0
$\begingroup$

This question already has an answer here:

I couldn't answer this question. This only one. It looks simple, but I got stuck. Here is the image of the question. The number $12$. Sorry for my english.

Prove that if the $\mathrm{ord}(p)a=3$, then $\mathrm{ord}(p)(a+1)=6$

Example: $3^3=1(\mathrm{mod}\;13)$ then $4^6=1(\mathrm{mod\;}13)$.

Prove that if the $\mathrm{ord}(p)a=3$, then $\mathrm{ord}(p)(a+1)=6$

$\endgroup$

marked as duplicate by Dietrich Burde, Juniven, Daniel W. Farlow, kingW3, user26857 Apr 4 '17 at 16:24

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

1
$\begingroup$

Hint: We have $a^3 - 1=(a-1)(a^2+a+1)$.

$\endgroup$

Not the answer you're looking for? Browse other questions tagged or ask your own question.