We were given a 3 x 3 matrix,

1 2 0

-1 -1 1

0 1 1

We are asked

a) the characteristic polynomial of A.

b) eigenvalues of A.

c) the basis for each eigenspace of A.

d) the algebraic and geometric multiplicity of each eigenvalue.

Parenthesis are the book answers.

I don't know what I did wrong for a & b

a) I did the crossproduct and got -3L^3 + L^2 + L - 1 (-L^3 + L^2)

b) L = 1,1 (L=0,1)

c) I know how to get this, but I need the right eigenvalues...

d) I have no idea what this means, could someone explain?