EigenVectors system of differentials

dp182
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Homework Statement


Find the general solution for the following systems of equations
( 2 0 )
( 0 2 )

Homework Equations


(A-Ix)
c1e^at[]+c2e^bt[]


The Attempt at a Solution


when attempting to find the eigenvalues I come up with (2) so plugging back into get the vectors you come up with a zero matrix how do i get vectors from it do i just pick any ones
 
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For any vector, \begin{bmatrix}x \\ y\end{bmatrix}, in R2,
\begin{bmatrix}2 & 0 \\ 0 & 2\end{bmatrix}\begin{bmatrix}x \\ y\end{bmatrix}= \begin{bmatrix}2x \\ 2y\end{bmatrix}

so that any vector is an eigenvector.

That's why you can just choose any two independent vectors as a basis for the eigenspace.

Of course
\begin{bmatrix}1 \\ 0 \end{bmatrix}
and
\begin{bmatrix}0 \\ 1 \end{bmatrix}
are the "standard" choice.
 
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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