rid4

Se eseguiamo il prodotto tra le matrici otteniamo:

$\begin{displaymath} \left( \begin{array}{ccc} x' & y' & 1 \end{array} \righ... ... \left( \begin{array}{c} x'\\ y'\\ 1 \end{array} \right)= \end{displaymath}$

$\begin{displaymath} =\left( \begin{array}{ccc} x' & y' & 1 \end{array} \rig... ... \left( \begin{array}{c} x'\\ y'\\ 1 \end{array} \right)= \end{displaymath}$

$\begin{displaymath} =\left( \begin{array}{ccc} x' & y' & 1 \end{array} \rig... ...{array}{c} x'\\ y'\\ 1 \end{array} \right)=0. \vspace{3mm} \end{displaymath}$

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