can a matrix be diagonalized if it has an eigenvalue of 0? I know that the diagonal must be invertible for this to happen but (yesterday I was solving a problem, a 3x3 matrix and I got 3 eigenvalues, 2 of which were 0, but if the two are 0, then the diagonal would look something like x 0 0/ 000/ 000 which I dont think is invertible... Am I going wrong somewhere? Also, if we were to find A^k=P^-1D^KP and we have such a matrix wouldnt we get an incorrect answer for A^K? I have a feeling I am missing something...