0,5x^2 – 3x + 4 = 0
D = b^2 – 4 * a * c = (– 3)^2 – 4 * 0.5 * 4 = 9 – 8 = 1
x1 = (–b + корень из D) / (2 * a) = (3 + 1) / (2 * 0.5) = 4 / 1 = 4
x2 = (–b – корень из D) / (2 * a) = (3 – 1) / (2 * 0.5) = 2 / 1 = 2
Ответ: 4; 2
3x^2 – 6x –9 = 0
D = (– 6)^2 – 4 * 3 * (– 9) = 36 + 108 = 144
x1 = (6 + 12) / (2 * 3) = 18 / 6 = 3
x2 = (6 – 12) / (2 * 3) = (– 6) / 6 = -1
Ответ: 3; –1