What is the significance of Eigenvalues in a 2 by 2 matrix?

rocomath
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Assuming 2 by 2.

Ok, I'm asked to find the Eigenvalues. How do I know which should be lambda 1 and lambda 2? I can find the lambda's easily, but does it matter which is 1 or 2? It becomes important when I'm asked to diagonalize.

A=S\Lambda S^{-1}
 
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The order is not important when you diagonalize.
 


matt grime said:
The order is not important when you diagonalize.
Thanks matt! Now I can go back to studying :)
 


Swapping \lambda_1 and \lambda_2 will swap their positions on the diagonal but either way is a valid diagonalization.
 
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