|λE-A| =
|λ-1 -1 -3|
| 0 λ-3 0|
|-2 -2 λ|
|λE-A| = (λ-3)*
|λ-1 -3|
|-2 λ|
|λE-A| = (λ-3)(λ^2-λ-6) = (λ+2)(λ-3)^2
特征值 λ = -2, 3, 3
对于 λ = -2, λE-A =
[-3 -1 -3]
[ 0 -5 0]
[-2 -2 -2]
行初等变换为
[ 1 1 1]
[ 0 1 0]
[ 0 2 0]
行初等变换为
[ 1 0 1]
[ 0 1 0]
[ 0 0 0]
得特征向量 (1 0 -1)^T