Question

sendo A=[3 2 6] , determinar
[4 9 8]

a)A.I3.
b)I2.A

Answer 1

a)

$A*I_3= \left[\begin{array}{ccc}3&2&6\\4&9&5\end{array}\right] * \left[\begin{array}{ccc}1&0&0\\0&1&0\\0&0&1\end{array}\right] \\\\\\A*I_3=\left[\begin{array}{ccc}(3+0+0)&(0+2+0)&(0+0+6)\\(4+0+0)&(0+9+0)&(0+0+5)\end{array}\right]\\\\\\A*I_3=\left[\begin{array}{ccc}3&2&6\\4&9&5\end{array}\right]$

b)

$I_2*A= \left[\begin{array}{cc}1&0\\0&1\end{array}\right]*\left[\begin{array}{ccc}3&2&6\\4&9&5\end{array}\right] \\\\\\I_2*A=\left[\begin{array}{ccc}(3+0)&(2+0)&(6+0)\\(0+4)&(0+9)&(0+5)\end{array}\right]\\\\\\I_2*A=\left[\begin{array}{ccc}3&2&6\\4&9&5\end{array}\right]$