Eigenvalues? DO I have the right idea with this problem?

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Homework Statement



I'm supposed to find all the eigenvalues for this 2x2 matrix:

0 2
3 0

Homework Equations


The Attempt at a Solution



When I tried to do it with no row interchanges, I got the characteristic characteristic equation:
λ2-6=0

So, instead of solving this, I interchanged the rows of my matrix to get:

3 0
0 2
And then my determinant would be negative right? I got λ=2,3...I was wondering if I did this right?

Any help is appreciated, thanks.
 
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SMA_01 said:

Homework Statement



I'm supposed to find all the eigenvalues for this 2x2 matrix:

0 2
3 0

Homework Equations





The Attempt at a Solution



When I tried to do it with no row interchanges, I got the characteristic characteristic equation:
λ2-6=0
Which means that the eigenvalues are ±√6.
SMA_01 said:
So, instead of solving this, I interchanged the rows of my matrix to get:

3 0
0 2
And then my determinant would be negative right? I got λ=2,3...I was wondering if I did this right?
The latter part is wrong.

The determinant you are investigating is
\begin{vmatrix}-\lambda & 2 \\ 3 & -\lambda \end{vmatrix}

not
\begin{vmatrix}0 & 2 \\ 3 & 0 \end{vmatrix}
 
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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