Question

$\left[\begin{array}{ccc}1&2&3\\4&5&6\\7&8&9\end{array}\right] \left[\begin{array}{ccc}1&2&3\\4&5&6\\7&8&9\end{array}\right] x^{2} \sqrt{x} \neq \left \{ {{y=2} \atop {x=2}} \right. \leq \frac{x}{y} x_{123} 3\sqrt[n]{x}$

Answer 1

$\mathbb\red{ \tiny A \scriptsize \: N \small \:S \large \: W \Large \:E \huge \: R}$

$\rule{300pt}{0.1pt}$

$\\ \left[\begin{array}{ll}1 & 2 & 3 \\ 4 & 5 & 6 \\ 7 & 8 & 9\end{array}\right]\left[\begin{array}{ll}1 & 2 & 3 \\ 4 & 5 & 6 \\ 7 & 8 & 9\end{array}\right]$

$\\ \\ =\left[\begin{array}{cc}1+8+21 & 2+10+24 & 13+12+27 \\ 4+20+42 & 8+25+48 & 12+30+54 \\ 7+32+63 & 14+40+72 & 21+48+81\end{array}\right]$

$\\ \\ =\left[\begin{array}{cc}9+21 & 12+24 & 15+27 \\ 24+42 & 33+48 & 42+54 \\ 39+63 & 54+72 & 69+81\end{array}\right]$

$\\ \\ \color{olive}\bigstar \boxed{ \left[\begin{array}{ll}1 & 2 & 3 \\ 4 & 5 & 6 \\ 7 & 8 & 9\end{array}\right]\left[\begin{array}{ll}1 & 2 & 3 \\ 4 & 5 & 6 \\ 7 & 8 & 9\end{array}\right] =\left[\begin{array}{ccc}30 & 36 & 42 \\ 66 & 81 & 96 \\ 102 & 126 & 150\end{array}\right] }\bigstar$