Find eigenvectors of matrix:
$$ A = \left[ \begin{matrix}-1&1\\-1&-3\end{matrix} \right] $$The eigenvectors and eigenvalues of matrix A are:
Eigenvalue | Eigenvector |
$ -2 $ | $ \begin{bmatrix} 1 \cr -1 \end{bmatrix} $ |
$ -2 $ | $ \begin{bmatrix} 1 \cr -1 \end{bmatrix} $ |
Step 1 : Find characteristic polynomial $ p(\lambda) $:
$$ p(\lambda) = \lambda^2+4\lambda+4 $$Step 2 : Find the eigenvalues by solving the characteristic equation $ \lambda^2+4\lambda+4 = 0. $
The eigenvalues are
$$ \lambda_1 = -2 ~ , ~ \lambda_2 = -2 $$( click here to view an explanation on how to solve this equation.)
Step 3 : To find the associated eigenvectors ( $ x $ ), we have to solve the equation $ A x = \lambda I $.
For $ \lambda_ 0 = -2 $ we have $ A x = -2 I $.