Wronskian to determine lin.ind. of solutions to a system of ODEs

SithsNGiggles
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Homework Statement



In my book, I'm given that ##\vec{x}_1=\left(\begin{matrix}t^2\\t\end{matrix}\right), \vec{x}_2=\left(\begin{matrix}0\\1+t\end{matrix}\right), \vec{x}_3=\left(\begin{matrix}-t^2\\1\end{matrix}\right)## are solutions. My textbook presents an algebraic way to show that the vectors are linear independent, but I was hoping to see if I can use the Wronskian to show the same result.

Homework Equations



The Attempt at a Solution



I thought this was how the Wronskian would look:
##W\left(\vec{x}_1, \vec{x}_2, \vec{x}_3\right)=

\left|\begin{matrix}

\left(\begin{matrix}t^2\\1\end{matrix}\right) & \left(\begin{matrix}0\\1+t\end{matrix}\right) & \left(\begin{matrix}-t^2\\1\end{matrix}\right)\\

\left(\begin{matrix}2t\\0\end{matrix}\right) & \left(\begin{matrix}0\\1\end{matrix}\right) & \left(\begin{matrix}-2t\\0\end{matrix}\right)\\

\left(\begin{matrix}2\\0\end{matrix}\right) & \left(\begin{matrix}0\\0\end{matrix}\right) & \left(\begin{matrix}-2\\0\end{matrix}\right)
\end{matrix}\right|##

But I couldn't see how to proceed from there, since matrix multiplication won't work. How would I find this determinant?
 
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You can't because it doesn't make sense.

In any case, you should be able to see by inspection that the three vectors aren't linearly independent.
 
Okay, thanks.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...

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