$$$\left[\begin{array}{ccc}\frac{\sqrt{6}}{6} & \frac{\sqrt{6}}{6} & \frac{\sqrt{6}}{3}\\\frac{\sqrt{3}}{3} & \frac{\sqrt{3}}{3} & - \frac{\sqrt{3}}{3}\\\frac{\sqrt{2}}{2} & - \frac{\sqrt{2}}{2} & 0\end{array}\right]\cdot \left[\begin{array}{ccc}1 & 3 & 5\\1 & 3 & 1\\2 & -1 & 7\end{array}\right]$$$

计算 $$$\left[\begin{array}{ccc}\frac{\sqrt{6}}{6} & \frac{\sqrt{6}}{6} & \frac{\sqrt{6}}{3}\\\frac{\sqrt{3}}{3} & \frac{\sqrt{3}}{3} & - \frac{\sqrt{3}}{3}\\\frac{\sqrt{2}}{2} & - \frac{\sqrt{2}}{2} & 0\end{array}\right]\cdot \left[\begin{array}{ccc}1 & 3 & 5\\1 & 3 & 1\\2 & -1 & 7\end{array}\right]$$$。

$$$\left[\begin{array}{ccc}{\color{Brown}\frac{\sqrt{6}}{6}} & {\color{BlueViolet}\frac{\sqrt{6}}{6}} & {\color{GoldenRod}\frac{\sqrt{6}}{3}}\\{\color{Purple}\frac{\sqrt{3}}{3}} & {\color{OrangeRed}\frac{\sqrt{3}}{3}} & {\color{DeepPink}- \frac{\sqrt{3}}{3}}\\{\color{DarkMagenta}\frac{\sqrt{2}}{2}} & {\color{Crimson}- \frac{\sqrt{2}}{2}} & {\color{DarkCyan}0}\end{array}\right]\cdot \left[\begin{array}{ccc}{\color{Red}1} & {\color{BlueViolet}3} & {\color{Brown}5}\\{\color{Violet}1} & {\color{DarkMagenta}3} & {\color{Purple}1}\\{\color{Crimson}2} & {\color{SaddleBrown}-1} & {\color{Blue}7}\end{array}\right] = \left[\begin{array}{ccc}{\color{Brown}\left(\frac{\sqrt{6}}{6}\right)}\cdot {\color{Red}\left(1\right)} + {\color{BlueViolet}\left(\frac{\sqrt{6}}{6}\right)}\cdot {\color{Violet}\left(1\right)} + {\color{GoldenRod}\left(\frac{\sqrt{6}}{3}\right)}\cdot {\color{Crimson}\left(2\right)} & {\color{Brown}\left(\frac{\sqrt{6}}{6}\right)}\cdot {\color{BlueViolet}\left(3\right)} + {\color{BlueViolet}\left(\frac{\sqrt{6}}{6}\right)}\cdot {\color{DarkMagenta}\left(3\right)} + {\color{GoldenRod}\left(\frac{\sqrt{6}}{3}\right)}\cdot {\color{SaddleBrown}\left(-1\right)} & {\color{Brown}\left(\frac{\sqrt{6}}{6}\right)}\cdot {\color{Brown}\left(5\right)} + {\color{BlueViolet}\left(\frac{\sqrt{6}}{6}\right)}\cdot {\color{Purple}\left(1\right)} + {\color{GoldenRod}\left(\frac{\sqrt{6}}{3}\right)}\cdot {\color{Blue}\left(7\right)}\\{\color{Purple}\left(\frac{\sqrt{3}}{3}\right)}\cdot {\color{Red}\left(1\right)} + {\color{OrangeRed}\left(\frac{\sqrt{3}}{3}\right)}\cdot {\color{Violet}\left(1\right)} + {\color{DeepPink}\left(- \frac{\sqrt{3}}{3}\right)}\cdot {\color{Crimson}\left(2\right)} & {\color{Purple}\left(\frac{\sqrt{3}}{3}\right)}\cdot {\color{BlueViolet}\left(3\right)} + {\color{OrangeRed}\left(\frac{\sqrt{3}}{3}\right)}\cdot {\color{DarkMagenta}\left(3\right)} + {\color{DeepPink}\left(- \frac{\sqrt{3}}{3}\right)}\cdot {\color{SaddleBrown}\left(-1\right)} & {\color{Purple}\left(\frac{\sqrt{3}}{3}\right)}\cdot {\color{Brown}\left(5\right)} + {\color{OrangeRed}\left(\frac{\sqrt{3}}{3}\right)}\cdot {\color{Purple}\left(1\right)} + {\color{DeepPink}\left(- \frac{\sqrt{3}}{3}\right)}\cdot {\color{Blue}\left(7\right)}\\{\color{DarkMagenta}\left(\frac{\sqrt{2}}{2}\right)}\cdot {\color{Red}\left(1\right)} + {\color{Crimson}\left(- \frac{\sqrt{2}}{2}\right)}\cdot {\color{Violet}\left(1\right)} + {\color{DarkCyan}\left(0\right)}\cdot {\color{Crimson}\left(2\right)} & {\color{DarkMagenta}\left(\frac{\sqrt{2}}{2}\right)}\cdot {\color{BlueViolet}\left(3\right)} + {\color{Crimson}\left(- \frac{\sqrt{2}}{2}\right)}\cdot {\color{DarkMagenta}\left(3\right)} + {\color{DarkCyan}\left(0\right)}\cdot {\color{SaddleBrown}\left(-1\right)} & {\color{DarkMagenta}\left(\frac{\sqrt{2}}{2}\right)}\cdot {\color{Brown}\left(5\right)} + {\color{Crimson}\left(- \frac{\sqrt{2}}{2}\right)}\cdot {\color{Purple}\left(1\right)} + {\color{DarkCyan}\left(0\right)}\cdot {\color{Blue}\left(7\right)}\end{array}\right] = \left[\begin{array}{ccc}\sqrt{6} & \frac{2 \sqrt{6}}{3} & \frac{10 \sqrt{6}}{3}\\0 & \frac{7 \sqrt{3}}{3} & - \frac{\sqrt{3}}{3}\\0 & 0 & 2 \sqrt{2}\end{array}\right]$$$

$$$\left[\begin{array}{ccc}\frac{\sqrt{6}}{6} & \frac{\sqrt{6}}{6} & \frac{\sqrt{6}}{3}\\\frac{\sqrt{3}}{3} & \frac{\sqrt{3}}{3} & - \frac{\sqrt{3}}{3}\\\frac{\sqrt{2}}{2} & - \frac{\sqrt{2}}{2} & 0\end{array}\right]\cdot \left[\begin{array}{ccc}1 & 3 & 5\\1 & 3 & 1\\2 & -1 & 7\end{array}\right] = \left[\begin{array}{ccc}\sqrt{6} & \frac{2 \sqrt{6}}{3} & \frac{10 \sqrt{6}}{3}\\0 & \frac{7 \sqrt{3}}{3} & - \frac{\sqrt{3}}{3}\\0 & 0 & 2 \sqrt{2}\end{array}\right]\approx \left[\begin{array}{ccc}2.449489742783178 & 1.632993161855452 & 8.16496580927726\\0 & 4.04145188432738 & -0.577350269189626\\0 & 0 & 2.82842712474619\end{array}\right]$$$A