Solve this$f(A)=A^{3}+4 A^{2}-A$
Question:
If $f(x)=x^{3}+4 x^{2}-x$, find $f(A)$, where $A=\left[\begin{array}{rrr}0 & 1 & 2 \\ 2 & -3 & 0 \\ 1 & -1 & 0\end{array}\right]$
Solution:
Given : $f(x)=x^{3}+4 x^{2}-x$