Răspuns:
6
Explicație pas cu pas:
[tex] f(x) = 0 \\\\ -x^2 + 2x + 8 = 0\\\\ \Delta = 4 - 4\cdot 8 \cdot (-1) = 4 + 32 = 36\implies \sqrt{\Delta} = \sqrt{36} = 6\\\\x_{1,2} = \frac{-2\pm 6}{-2} = 1 \pm 3\\\\\implies x_1 = -2\\\\\implies x_2 = 4\\\\\textrm{Distanta dintre ele } = |x_1 - x_2| = |-2 - 4| = |-6| = \boxed{6}[/tex]
