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

  • Thread starter Thread starter SMA_01
  • Start date Start date
  • Tags Tags
    Eigenvalues Idea
Join the discussion
Registration is free. Ask a follow-up in this thread, or start your own.
1 reply · 1K views
SMA_01
Messages
215
Reaction score
0

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.
 
Physics news on Phys.org
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
[tex]\begin{vmatrix}-\lambda & 2 \\ 3 & -\lambda \end{vmatrix}[/tex]

not
[tex]\begin{vmatrix}0 & 2 \\ 3 & 0 \end{vmatrix}[/tex]