
Yefim S. answered 07/27/20
Math Tutor with Experience
det(B - λE) = (1 - λ)2(5 - λ) + 8 + 8 - 4(5 - λ) + 4(1 - λ) + 4(1 - λ) = 0;
(λ2 - 2λ - 3)(5 - λ) + 16 + 8(1 - λ) = 0; 5λ2 - 10λ - 15 - λ3 + 2λ2 + 3λ + 24 - 8λ = 0;λ
λ3 - 7λ2 + 15λ - 9 = 0
Using rational zeros therem: lisr of possible zeros ± 1, ±3, ±9.
And we have λ = 1, λ = 3 and λ = 3.
So igenvectors: for λ = 1 [(0 2 2) (-2 4 2) (2 - 2 0)][x y z] = [0 0 0] and we get system:-2y + 2z = 0, 2x + 4y - 2z = 0, 2x + 2y = 0 so y = - x, z = -x and igenvector for λ = 1 is (-1, 1, 1).
If λ = 3 we have [(-2 2 2) (- 2 2 2) (2 - 2 - 2)]{x y z] = [0 0 0] and we get 3 equations: -2x - 2y + 2z = 0,
2x + 2y - 2z = 0 and 2x + 2y - 2z = 0 or just one equation x + y - z = 0 and we have 2 igenvectors:
(1, 0, 1) and (0, 1, 1)