Quadratic Congruences Mod 8: How to Solve?

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SUMMARY

To solve the quadratic congruence \(x^2 + 2x - 3 \equiv 0 \mod 8\), one can rewrite it as \(x^2 + 2x \equiv 3 \mod 8\). The solution involves testing all possible candidates for \(x\) within the range of 0 to 7, as there are only 8 potential values modulo 8. This method is applicable for nth degree congruences, although the discussion suggests that no specific approach exists for them beyond testing candidates.

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Homework Statement



Hello everyone!

How would you solve a quadratic or nth degree congruence? For example how would I solve:


(x^2) + 2x -3 = 0 (mod 8 )


The Attempt at a Solution



I know this can be written like:

(x^2) + 2x = 3 (mod 8 ) but where would I go from here? and would I use the same approach for nth degree congruencies?

Thanks
 
Last edited:
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I don't think there is any approach for nth degree congruencies. mod 8 there are only 8 candidates for x. I suggest you try them all.
 

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