- #1
hahaha158
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Homework Statement
Find the eigenvalues
| 1 2 -1|
| -5 7 -5 |
| -9 8 -7|
Homework Equations
The Attempt at a Solution
I know that i need to add a -λ to every term in the trace so my matrix becomes
| 1-λ 2 -1|
| -5 7-λ -5|
| -9 8 -7-λ|
Then i need to take the determinant and find the values of λ when det=0
However i tried to do this without doing any shortcuts and ended up with an equation in terms of λ^3,λ^2,λ, and constants.
I am not sure how i can solve this, and i feel like there should be a shorter way to simplify the matrix at the start to make taking the determinant easier, but I'm not sure since there are no 0's i can use to simplify the determinant. Can anyone please help?
Thanks