# Thread: Eigenvalues

1. ## Eigenvalues

Can someone tell me how to continue from here? I'm stuck
p.s im usiing x for lambda

The matrix of the question is
1 0 -2
-4 -3 2
-1 -2 5

|xI - A| = 0,i get

(x-1) (0) ( 2)
(4) (x+3) -2
(1) (1) (x-5)

Determinant calculation I get
(x-1)(x*2 -2x -13) + (2-2x)

Then I'm stuck here,dont know how to continue.
can someone guide me from here??? The answer i got using the online calculator gave the eigenvalues to be -3,1 & 5.

Pls help..tq...

2. (x–1)(x*2 –2x –13) + (2-2x) = (x–1)(x*2 –2x –13) –2(x–1). Does that give you a hint how to continue?

3. Thanks a lot man.Managed to solve it, but i keep geting different cvalues for eigenvectors, its half of the original answer.

Thank you for guiding.

4. Originally Posted by anderson
Managed to solve it, but i keep geting different cvalues for eigenvectors, its half of the original answer.
Hmm, I didn't think to check your original working. There's something wrong at an earlier stage.

Originally Posted by anderson
The matrix of the question is
1 0 -2
-4 -3 2
-1 -2 5

|xI - A| = 0,i get

(x-1) (0) ( 2)
(4) (x+3) -2
(1) (2) (x-5) (You had a 1 there.)