Diagonaliseation a square matrix of any order.

Let A be a square matrix of order n. Then (A - kI)X = 0, where k is called eigen value and I is called Identity matrix of order n, X is called eigen vector, is called characterstic equation. The equation A - kI = 0 gives n values of k and for each value of k, n column vectors. P be the square matrix of order n formed by the n column vectors.

The diagonal matrix of A = (inverse of P)AP.