Question

I need help to diagonalize this matrix.

Answer 1

{{-1, 1, -1}, {-1, 0, 0}, {0, 1, 2}}
His minimal polynomial is:
x^3-x^2-x-3=0
But I don't know how to find the roots of this equation in analitic form (I know how to find an aproximate form but this isn't useful).

Answer 2

I'll search in the web the equation to find the roots of 3rd grade polynomic equations, I know there's one to grade 3 and one to grade 4 (5th and higher doens't exist).

Answer 3

I used this (Is in Spanish)
http://gaussianos.com/la-semana-de-la-cubica-solucion-de-problema-con-bonus-cuartico/
Finally it wasn't a problem with the diagonialization but to factorice the polynomial.
It coincides with:
http://www.wolframalpha.com/input/?i= {{-1%2C+1%2C+-1}%2C+{-1%2C+0%2C+0}%2C+{0%2C+1%2C+2}}&dataset=

Answer 4

http://openstudy.com/study#/updates/50b20208e4b09749ccac8662
might help your cause..