Teoria delle quadriche

(1.1) :

$\displaystyle f(x,y,z)$	$\displaystyle =$	$\displaystyle a_{11}x^2+a_{22}y^2+a_{33}z^2+2a_{12}xy+2a_{13}xz+$
		$\displaystyle +a_{23}yz+2a_{01}x+2a_{02}y+2a_{03}z+a_{00} \; = \; 0$

(1.2) :

$\displaystyle \left( \begin{array}{cccc} 1 & x & y & z\\ \end{array} \rig... ...al{A} \left( \begin{array}{c} 1 \\ x \\ y \\ z\\ \end{array} \right)=0$