Computing eigenvalues and eigenvectors

jinksys
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Find the characteristic polynomial, eigenvectors, and eigenvalues of the matrix.

Code:
[
2 -2 3
0 3 -2
0 -1 2
]

My characteristic poly is x^3 - 7x^2 + 14x - 8

The roots are 1, 2, and 4.

When solving the system, (2I - A)x = 0 I get:
Code:
[
0 1 0 0 
0 0 1 0 
0 0 0 0 
]

Can someone tell me how this relates to a solution?

It looks like x2 and x3 would be zero, but what about x1?
 
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This means that (t 0 0) is an eigenvector for any t. Since constant multiples of eigenvectors are also eigenvectors, typically we would say that (1 0 0) is the eigenvector (associated with the eigenvalue 2).
 
Thanks, that makes sense.
 
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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