x^2-x-6=0

$${{\mathtt{x}}}^{{\mathtt{2}}}{\mathtt{\,-\,}}{\mathtt{x}}{\mathtt{\,-\,}}{\mathtt{6}} = {\mathtt{0}}$$

$${\mathtt{x}} = {\mathtt{0.5}}{\mathtt{\,\small\textbf+\,}}{\sqrt{{{\mathtt{0.5}}}^{{\mathtt{2}}}{\mathtt{\,\small\textbf+\,}}{\mathtt{6}}}}$$

$${\mathtt{x}} = {\mathtt{0.5}}{\mathtt{\,\small\textbf+\,}}{\sqrt{{\mathtt{6.25}}}}$$               =>    x1 =  0.5 +2.5 = 3

                                            =>    x2  =  0.5 -2.5  = -2

 x² - x -6 = (x + 2)*(x - 3 )

(x+2)*(x-3) = 0                =>    x1 = -2      and   x2 = +3

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Gruß radix !