Question

( begin{array}{l}A=left[begin{array}{cc}7 & -14 4 & -8end{array}right] & begin{array}{r}A^{2}=left[begin{array}{cc}7 & -14 4 & -8end{array}right]left[begin{array}{cc}7 & -14 4 & -8end{array}right] A^{3}=A^{2} cdot A & =left(begin{array}{cc}-7 & 4 -4 & 8end{array}right) & =left[begin{array}{cc}-7 & 14 -4 & 8end{array}right]left[begin{array}{cc}7 & -14 4 & -8end{array}right] & =left[begin{array}{cc}7 & -14 4 & -8end{array}right]end{array} therefore quad A^{3}=Aend{array} )

# If A-7 -147 24 1, show that A3 = A. -85

Solution