Ponderable 2.2.1

$\left[\begin{array}{ccc}0& 1& 0\\ 1& 0& 0\\ 0& 0& 1\end{array}\right]\left[\begin{array}{c}x\\ y\\ z\end{array}\right]=\left[\begin{array}{c}\mathrm{0.x+1.y+0.z}\\ \mathrm{1.x+0.y+0.z}\\ \mathrm{0.x+0.y+1.z}\end{array}\right]=\left[\begin{array}{c}y\\ x\\ z\end{array}\right]$, QED.

Maison