1. Решите уравнение: a) 5x² – 20 = 0; б) x² – 5x – 24 = 0; в) 7x² – 22x + 3 = 0.

a) 5x² – 20 = 0 5x² = 20 x² = 4 x₁ = 2, x₂ = -2 Ответ: x₁ = 2, x₂ = -2 б) x² – 5x – 24 = 0 D = (-5)² - 4 * 1 * (-24) = 25 + 96 = 121 x₁ = (5 + √121) / 2 = (5 + 11) / 2 = 16 / 2 = 8 x₂ = (5 - √121) / 2 = (5 - 11) / 2 = -6 / 2 = -3 Ответ: x₁ = 8, x₂ = -3 в) 7x² – 22x + 3 = 0 D = (-22)² - 4 * 7 * 3 = 484 - 84 = 400 x₁ = (22 + √400) / (2 * 7) = (22 + 20) / 14 = 42 / 14 = 3 x₂ = (22 - √400) / (2 * 7) = (22 - 20) / 14 = 2 / 14 = 1 / 7 Ответ: x₁ = 3, x₂ = 1/7