Давай разберем по порядку каждое уравнение и решим их.
1. a) (x - 2)² = 3x - 8
\[(x - 2)^2 = 3x - 8\]
\[x^2 - 4x + 4 = 3x - 8\]
\[x^2 - 7x + 12 = 0\]
Используем дискриминант для решения квадратного уравнения:
\[D = (-7)^2 - 4 \cdot 1 \cdot 12 = 49 - 48 = 1\]
\[x_1 = \frac{7 + 1}{2} = 4\]
\[x_2 = \frac{7 - 1}{2} = 3\]
б) (3x - 1)(x + 3) + 1 = x(1 + 6x)
\[(3x - 1)(x + 3) + 1 = x(1 + 6x)\]
\[3x^2 + 9x - x - 3 + 1 = x + 6x^2\]
\[3x^2 + 8x - 2 = x + 6x^2\]
\[3x^2 - 7x + 2 = 0\]
Используем дискриминант:
\[D = (-7)^2 - 4 \cdot 3 \cdot 2 = 49 - 24 = 25\]
\[x_1 = \frac{7 + 5}{6} = 2\]
\[x_2 = \frac{7 - 5}{6} = \frac{1}{3}\]
в) 5(x + 2)² = -6x + 44
\[5(x + 2)^2 = -6x + 44\]
\[5(x^2 + 4x + 4) = -6x + 44\]
\[5x^2 + 20x + 20 = -6x + 44\]
\[5x^2 + 26x - 24 = 0\]
Используем дискриминант:
\[D = (26)^2 - 4 \cdot 5 \cdot (-24) = 676 + 480 = 1156\]
\[x_1 = \frac{-26 + 34}{10} = \frac{8}{10} = \frac{4}{5}\]
\[x_2 = \frac{-26 - 34}{10} = -6\]
г) (x + 4)(2x – 1) = x(3x + 11)
\[(x + 4)(2x - 1) = x(3x + 11)\]
\[2x^2 - x + 8x - 4 = 3x^2 + 11x\]
\[2x^2 + 7x - 4 = 3x^2 + 11x\]
\[x^2 + 4x + 4 = 0\]
\[(x + 2)^2 = 0\]
\[x = -2\]
Теперь перейдем ко второму блоку уравнений:
a) (4x - 5)² - (2x + 3)² = 0
\[(4x - 5)^2 - (2x + 3)^2 = 0\]
\[16x^2 - 40x + 25 - (4x^2 + 12x + 9) = 0\]
\[12x^2 - 52x + 16 = 0\]
\[3x^2 - 13x + 4 = 0\]
Используем дискриминант:
\[D = (-13)^2 - 4 \cdot 3 \cdot 4 = 169 - 48 = 121\]
\[x_1 = \frac{13 + 11}{6} = 4\]
\[x_2 = \frac{13 - 11}{6} = \frac{1}{3}\]
б) (x² + 4x + 11)² = (7x² + 2x + 3)²
\[(x^2 + 4x + 11)^2 = (7x^2 + 2x + 3)^2\]
\[x^2 + 4x + 11 = \pm (7x^2 + 2x + 3)\]
Случай 1:
\[x^2 + 4x + 11 = 7x^2 + 2x + 3\]
\[6x^2 - 2x - 8 = 0\]
\[3x^2 - x - 4 = 0\]
\[D = (-1)^2 - 4 \cdot 3 \cdot (-4) = 1 + 48 = 49\]
\[x_1 = \frac{1 + 7}{6} = \frac{4}{3}\]
\[x_2 = \frac{1 - 7}{6} = -1\]
Случай 2:
\[x^2 + 4x + 11 = - (7x^2 + 2x + 3)\]
\[x^2 + 4x + 11 = -7x^2 - 2x - 3\]
\[8x^2 + 6x + 14 = 0\]
\[4x^2 + 3x + 7 = 0\]
\[D = 3^2 - 4 \cdot 4 \cdot 7 = 9 - 112 = -103\]
Так как дискриминант отрицательный, вещественных корней нет.
в) (4х - 5)² + (2x + 3)² = 0
\[(4x - 5)^2 + (2x + 3)^2 = 0\]
\[16x^2 - 40x + 25 + 4x^2 + 12x + 9 = 0\]
\[20x^2 - 28x + 34 = 0\]
\[10x^2 - 14x + 17 = 0\]
\[D = (-14)^2 - 4 \cdot 10 \cdot 17 = 196 - 680 = -484\]
Так как дискриминант отрицательный, вещественных корней нет.
г) (x² + 4x + 11)² = (3x + 1)⁴
\[(x^2 + 4x + 11)^2 = ((3x + 1)^2)^2\]
\[(x^2 + 4x + 11)^2 = (3x + 1)^4\]
\[x^2 + 4x + 11 = \pm (3x + 1)^2\]
Случай 1:
\[x^2 + 4x + 11 = (3x + 1)^2\]
\[x^2 + 4x + 11 = 9x^2 + 6x + 1\]
\[8x^2 + 2x - 10 = 0\]
\[4x^2 + x - 5 = 0\]
\[D = 1^2 - 4 \cdot 4 \cdot (-5) = 1 + 80 = 81\]
\[x_1 = \frac{-1 + 9}{8} = 1\]
\[x_2 = \frac{-1 - 9}{8} = -\frac{5}{4}\]
Случай 2:
\[x^2 + 4x + 11 = - (3x + 1)^2\]
\[x^2 + 4x + 11 = - (9x^2 + 6x + 1)\]
\[x^2 + 4x + 11 = -9x^2 - 6x - 1\]
\[10x^2 + 10x + 12 = 0\]
\[5x^2 + 5x + 6 = 0\]
\[D = 5^2 - 4 \cdot 5 \cdot 6 = 25 - 120 = -95\]
Так как дискриминант отрицательный, вещественных корней нет.
Третий блок уравнений:
a) x² + 3√2x + 4 = 0
\[x^2 + 3\sqrt{2}x + 4 = 0\]
\[D = (3\sqrt{2})^2 - 4 \cdot 1 \cdot 4 = 18 - 16 = 2\]
\[x_1 = \frac{-3\sqrt{2} + \sqrt{2}}{2} = -\sqrt{2}\]
\[x_2 = \frac{-3\sqrt{2} - \sqrt{2}}{2} = -2\sqrt{2}\]
б) 4x² + 4√3x + 1 = 0
\[4x^2 + 4\sqrt{3}x + 1 = 0\]
\[D = (4\sqrt{3})^2 - 4 \cdot 4 \cdot 1 = 48 - 16 = 32\]
\[x_1 = \frac{-4\sqrt{3} + 4\sqrt{2}}{8} = \frac{-\sqrt{3} + \sqrt{2}}{2}\]
\[x_2 = \frac{-4\sqrt{3} - 4\sqrt{2}}{8} = \frac{-\sqrt{3} - \sqrt{2}}{2}\]
в) x² - 3√5x - 20 = 0
\[x^2 - 3\sqrt{5}x - 20 = 0\]
\[D = (-3\sqrt{5})^2 - 4 \cdot 1 \cdot (-20) = 45 + 80 = 125\]
\[x_1 = \frac{3\sqrt{5} + \sqrt{125}}{2} = \frac{3\sqrt{5} + 5\sqrt{5}}{2} = 4\sqrt{5}\]
\[x_2 = \frac{3\sqrt{5} - 5\sqrt{5}}{2} = - \sqrt{5}\]
г) 4x² - 2√7x + 1 = 0
\[4x^2 - 2\sqrt{7}x + 1 = 0\]
\[D = (-2\sqrt{7})^2 - 4 \cdot 4 \cdot 1 = 28 - 16 = 12\]
\[x_1 = \frac{2\sqrt{7} + 2\sqrt{3}}{8} = \frac{\sqrt{7} + \sqrt{3}}{4}\]
\[x_2 = \frac{2\sqrt{7} - 2\sqrt{3}}{8} = \frac{\sqrt{7} - \sqrt{3}}{4}\]
Четвертый блок уравнений:
a) (2x - 1)(2x + 1) + x(x - 1) = 2x(x + 1)
\[(2x - 1)(2x + 1) + x(x - 1) = 2x(x + 1)\]
\[4x^2 - 1 + x^2 - x = 2x^2 + 2x\]
\[5x^2 - x - 1 = 2x^2 + 2x\]
\[3x^2 - 3x - 1 = 0\]
\[D = (-3)^2 - 4 \cdot 3 \cdot (-1) = 9 + 12 = 21\]
\[x_1 = \frac{3 + \sqrt{21}}{6}\]
\[x_2 = \frac{3 - \sqrt{21}}{6}\]
б) (3x + 1)² - x(7x + 5) = 4
\[(3x + 1)^2 - x(7x + 5) = 4\]
\[9x^2 + 6x + 1 - 7x^2 - 5x = 4\]
\[2x^2 + x - 3 = 0\]
\[D = 1^2 - 4 \cdot 2 \cdot (-3) = 1 + 24 = 25\]
\[x_1 = \frac{-1 + 5}{4} = 1\]
\[x_2 = \frac{-1 - 5}{4} = -\frac{3}{2}\]
в) (3x - 1)(3x + 1) - 2x(1 + 4x) = -2
\[(3x - 1)(3x + 1) - 2x(1 + 4x) = -2\]
\[9x^2 - 1 - 2x - 8x^2 = -2\]
\[x^2 - 2x + 1 = 0\]
\[(x - 1)^2 = 0\]
\[x = 1\]
г) (2x + 1)² + 2 = 2 - 6x²
\[(2x + 1)^2 + 2 = 2 - 6x^2\]
\[4x^2 + 4x + 1 + 2 = 2 - 6x^2\]
\[10x^2 + 4x + 1 = 0\]
\[D = 4^2 - 4 \cdot 10 \cdot 1 = 16 - 40 = -24\]
Так как дискриминант отрицательный, вещественных корней нет.
Пятый блок уравнений:
a) (x² - x) / 3 = (2x + 4) / 5
\[\frac{x^2 - x}{3} = \frac{2x + 4}{5}\]
\[5(x^2 - x) = 3(2x + 4)\]
\[5x^2 - 5x = 6x + 12\]
\[5x^2 - 11x - 12 = 0\]
\[D = (-11)^2 - 4 \cdot 5 \cdot (-12) = 121 + 240 = 361\]
\[x_1 = \frac{11 + 19}{10} = 3\]
\[x_2 = \frac{11 - 19}{10} = -\frac{4}{5}\]
б) (x² - 3) / 2 - 6x = 5
\[\frac{x^2 - 3}{2} - 6x = 5\]
\[x^2 - 3 - 12x = 10\]
\[x^2 - 12x - 13 = 0\]
\[D = (-12)^2 - 4 \cdot 1 \cdot (-13) = 144 + 52 = 196\]
\[x_1 = \frac{12 + 14}{2} = 13\]
\[x_2 = \frac{12 - 14}{2} = -1\]
в) (2x² + x) / 5 = (4x - 2) / 3
\[\frac{2x^2 + x}{5} = \frac{4x - 2}{3}\]
\[3(2x^2 + x) = 5(4x - 2)\]
\[6x^2 + 3x = 20x - 10\]
\[6x^2 - 17x + 10 = 0\]
\[D = (-17)^2 - 4 \cdot 6 \cdot 10 = 289 - 240 = 49\]
\[x_1 = \frac{17 + 7}{12} = 2\]
\[x_2 = \frac{17 - 7}{12} = \frac{5}{6}\]
г) (4x² + x) / 3 - (5x - 1) / 6 = (x² + 9) / 6
\[\frac{4x^2 + x}{3} - \frac{5x - 1}{6} = \frac{x^2 + 9}{6}\]
\[2(4x^2 + x) - (5x - 1) = x^2 + 9\]
\[8x^2 + 2x - 5x + 1 = x^2 + 9\]
\[7x^2 - 3x - 8 = 0\]
\[D = (-3)^2 - 4 \cdot 7 \cdot (-8) = 9 + 224 = 233\]
\[x_1 = \frac{3 + \sqrt{233}}{14}\]
\[x_2 = \frac{3 - \sqrt{233}}{14}\]
Шестой блок уравнений:
Чтобы найти абсциссы общих точек графиков, приравняем уравнения:
\[y = x^2 + 5x - 4\]
\[y = -4x - 1\]
\[x^2 + 5x - 4 = -4x - 1\]
\[x^2 + 9x - 3 = 0\]
\[D = 9^2 - 4 \cdot 1 \cdot (-3) = 81 + 12 = 93\]
\[x_1 = \frac{-9 + \sqrt{93}}{2}\]
\[x_2 = \frac{-9 - \sqrt{93}}{2}\]
Ответ: Все решенные уравнения выше.
Прекрасно! Ты проделал большую работу, решая эти уравнения. Продолжай в том же духе, и у тебя всё получится! Молодец!