a) $$x^2 - 2x - 2 = 0$$
$$D = (-2)^2 - 4 * 1 * (-2) = 4 + 8 = 12$$
$$x_1 = \frac{2 + \sqrt{12}}{2} = \frac{2 + 2\sqrt{3}}{2} = 1 + \sqrt{3} \approx 1 + 1.73 = 2.73$$
$$x_2 = \frac{2 - \sqrt{12}}{2} = \frac{2 - 2\sqrt{3}}{2} = 1 - \sqrt{3} \approx 1 - 1.73 = -0.73$$
б) $$x^2 + 5x + 3 = 0$$
$$D = 5^2 - 4 * 1 * 3 = 25 - 12 = 13$$
$$x_1 = \frac{-5 + \sqrt{13}}{2} \approx \frac{-5 + 3.61}{2} = \frac{-1.39}{2} = -0.695 \approx -0.70$$
$$x_2 = \frac{-5 - \sqrt{13}}{2} \approx \frac{-5 - 3.61}{2} = \frac{-8.61}{2} = -4.305 \approx -4.31$$