I need to solve for the eigenvalues of the matrix 1 -1 -1 1 3 2 -1 -1 0 So I subtract lambda I from the matrix and find the determinant I get: (1-x)(3-x)(-x)-(-1)(2)(-1)-(-1)(1)(-1)+(-1)(3-x)(-1)+(-1)(1)(-x)+(1-x)(2)(-1) = -x^3 + 4x^2 - x - 2 So (x-1) is a factor and then I get this remaining -(x^2-3x-2) which can't be factored..

Did I calculate the determinant wrongly?