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So I have the system of equations: $$ \begin{align*} 2a+3b+c-6d&= 1 \\ a-b+c+2d&=0\\ 3a+2b+3c-4d&=-1 \end{align*} $$

I have to prove that this system has no solutions. So, first I prove that all of them are linearly independent, this happens when the determinant is different from zero. I form the matrix $$ \begin{bmatrix} 2 & 3 & 1 \\ 1 & -1 & 1 \\ 3 & 2 & 3 \end{bmatrix} $$ and the determinant is indeed different from zero (It would take long to write it here). The system shouldn't have any solutions, so some of the vectors should be linearly independent as well. Can you form for me, the matrix that proves that they are linearly independent?

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    So, what was happened to $d$'s and their coefficients?2012-12-15
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    What is that ??2012-12-15
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    You have 3 equations but 4 parameters. Which of them are your unknown variables?2012-12-15
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    All of them? Why dont you just form the matrice for me,it is kinda urgent...please.2012-12-15
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    Why is it urgent? Is it an assignment? Or an exam problem?2012-12-15
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    No,its just that I have been trying to figure this out for like a hour...I dont know wheres my mistake and I have many other exercises..2012-12-15
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    Well, simply because this system does have a solution, it's parametric though.2012-12-15

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You will not be able to show that there are no solutions. Check out for example $a=\dfrac{9}{5}$, $b=-\dfrac{1}{5}$, $c=-2$, $d=0$.

I suggest going through the row reduction process.

Remark: If you really want to use a determinant, it can be done, though I don't advise it. But you could bring the $d$ stuff to the right hand side, treating $d$ as a parameter, and see what the determinant of the resulting $3\times 3$ tells you.

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    Sorry but this is the question on my textbook :/2012-12-15