设 $\boldsymbol{P}^{-1} \boldsymbol{A} \boldsymbol{P}=\boldsymbol{\Lambda}$, 其中 $\boldsymbol{P}=\left(\begin{array}{rr}-1 & -4 \\ 1 & 1\end{array}\right), \boldsymbol{\Lambda}=\left(\begin{array}{rr}-1 & 0 \\ 0 & 2\end{array}\right)$, 求 $\boldsymbol{A}^{11}$.