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Nov 27, 2016 at 12:11 vote accept Tomirio
Nov 27, 2016 at 6:39 history edited CurveEnthusiast CC BY-SA 3.0
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Nov 27, 2016 at 6:39 comment added CurveEnthusiast Oh and I see, I indeed made a typo. The "dividing with any number which has gcd non-zero" should of course be gcd not equal to one.
Nov 27, 2016 at 6:31 history edited CurveEnthusiast CC BY-SA 3.0
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Nov 26, 2016 at 19:45 comment added CurveEnthusiast Yes, every step you take is done in the ring $\mathbb{Z}/2002\mathbb{Z}$. So we can add and subtract rows, and multiply a specific rows with any integer. We can only divide a row by integers which are relatively prime to 2002.
Nov 26, 2016 at 19:42 comment added Tomirio Hmm, you're right. So at every indeterminate step, you will need to perform the $\mod(2002)$?
Nov 26, 2016 at 19:40 comment added CurveEnthusiast Consider for example the relation $\left(-5\right)^2=5^2$. If we follow your method, we obtain the matrix $M=\begin{pmatrix} 2 & 2\end{pmatrix}$. The tool will simplify this to the matrix $M=\begin{pmatrix} 1 & 1\end{pmatrix}$. But then the conclusion is that $-5=5$, which is incorrect.
Nov 26, 2016 at 19:38 comment added Tomirio I do perform the the Gaussian Elimination $\mod(2002)$. I only perform the $\mod(2002)$ when the Gaussian Elimination is done. You say that "dividing with any number which has $\gcd$ non-zero with 2002 is off-limits''. You can actually divide if the $\gcd$ of the number and 2002 equals 1, which means that the number has an inverse $\mod(2002)$
Nov 26, 2016 at 19:37 comment added CurveEnthusiast This online tool solves your system of equations over the complex numbers. This is not what you want. You want to have solutions in $\mathbb{Z}/2002\mathbb{Z}$.
Nov 26, 2016 at 19:26 comment added Tomirio Thanks for you answer! When I solve the matrix of the relations using some online tool, it gives me the exact same set of solutions as I calculate. So does WolframAlpha. The fact that I'm not ending up with any fraction after we row-reduced the matrix makes me think something else must be going wrong.
Nov 26, 2016 at 11:35 history answered CurveEnthusiast CC BY-SA 3.0