Question

Уравнение (х2 - 4х – 1) (х2 - 4х + 5) + 9 = 0 приведи к квадратному.
Найди решение данного уравнения.
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Answer 1

Объяснение:

х⁴-4х³+5х²-4х³+16х²-20х-х²+4х-4+9=х⁴-8х³+20х²-16х+4=0

Answer 2

$( {x}^{2} - 4x - 1)( {x}^{2} - 4x + 5) + 9 = 0 \\ {x}^{2} - 4x - 1 = y \\ {x}^{2} - 4x + 5 = y + 6 \\ {y}^{2} + 6y + 9 = 0$

$y1 = - 3 \\ y2 = 3$

${x}^{2} - 4x - 1 = - 3 \\ {x}^{2} - 4x+ 2 = 0\\ d = 16 - 4 \times 2 = 8 \\ x1 = \frac{4 - \sqrt{8} }{2} = \frac{2(2 - \sqrt{2} )}{2} = 2 - \sqrt{2 } \\ x2 = \frac{(4 + \sqrt{8} )}{2} = \frac{2(2 + \sqrt{2}) }{2} = 2 + \sqrt{2} \\$

${x}^{2} - 4x - 1 = 3 \\ {x}^{2} - 4x - 4 = 0 \\ d = 16 - 4 \times ( - 4) = 32 \\ x3 = \frac{4 - \sqrt{32} }{2} = \frac{4(1 - \sqrt{2} )}{2} = 2(1 - \sqrt{2}) \\ x4 = \frac{4 + \sqrt{32} }{2} = \frac{4(1 + \sqrt{2} )}{2} = 2(1 + \sqrt{2})$