1) 2x²-5x+2=0 2) 2x²-7x-4=0 3) 4x²-3x-1=0 4)-2x²+x+15=0 5)6x²+7x-5=0

Давай решим каждое квадратное уравнение по порядку, используя дискриминант. 1) 2x² - 5x + 2 = 0 * a = 2, b = -5, c = 2 * D = b² - 4ac = (-5)² - 4 * 2 * 2 = 25 - 16 = 9 * √D = √9 = 3 * x₁ = (-b + √D) / (2a) = (5 + 3) / (2 * 2) = 8 / 4 = 2 * x₂ = (-b - √D) / (2a) = (5 - 3) / (2 * 2) = 2 / 4 = 0.5 2) 2x² - 7x - 4 = 0 * a = 2, b = -7, c = -4 * D = b² - 4ac = (-7)² - 4 * 2 * (-4) = 49 + 32 = 81 * √D = √81 = 9 * x₁ = (-b + √D) / (2a) = (7 + 9) / (2 * 2) = 16 / 4 = 4 * x₂ = (-b - √D) / (2a) = (7 - 9) / (2 * 2) = -2 / 4 = -0.5 3) 4x² - 3x - 1 = 0 * a = 4, b = -3, c = -1 * D = b² - 4ac = (-3)² - 4 * 4 * (-1) = 9 + 16 = 25 * √D = √25 = 5 * x₁ = (-b + √D) / (2a) = (3 + 5) / (2 * 4) = 8 / 8 = 1 * x₂ = (-b - √D) / (2a) = (3 - 5) / (2 * 4) = -2 / 8 = -0.25 4) -2x² + x + 15 = 0 * a = -2, b = 1, c = 15 * D = b² - 4ac = (1)² - 4 * (-2) * 15 = 1 + 120 = 121 * √D = √121 = 11 * x₁ = (-b + √D) / (2a) = (-1 + 11) / (2 * -2) = 10 / -4 = -2.5 * x₂ = (-b - √D) / (2a) = (-1 - 11) / (2 * -2) = -12 / -4 = 3 5) 6x² + 7x - 5 = 0 * a = 6, b = 7, c = -5 * D = b² - 4ac = (7)² - 4 * 6 * (-5) = 49 + 120 = 169 * √D = √169 = 13 * x₁ = (-b + √D) / (2a) = (-7 + 13) / (2 * 6) = 6 / 12 = 0.5 * x₂ = (-b - √D) / (2a) = (-7 - 13) / (2 * 6) = -20 / 12 = -5/3

Ответ: Решения уравнений найдены выше.