Matrices Selectividad Castilla-León

Dadas las matrices

$P = \left( \begin{array}{ccc} 1 & 1 & 0\\ -1 & 0 & 1\\ -1 & -1 & 1 \end{array} \right)$
y
$A = \left( \begin{array}{ccc} -1 & 0 & 0\\ 0 & -1 & 0 \\ 0 & 0 & 2 \end{array} \right)$