Question

✓x+1 * ✓x+6 = 6
розв'язати рівняння​

Answer 1

$\sqrt{ x + 1} \times \sqrt{x + 6} = 6$

$\sqrt{(x + 1)(x + 6)} = 6$

$\sqrt{ {x}^{2} + 6x + x + 6} = 6$

$\sqrt{ {x}^{2} + 7x + 6 } = 6$

$( \sqrt{ {x}^{2} + 7x + 6} {)}^{2} = {6}^{2}$

${x}^{2} + 7x + 6 = 36$

${x}^{2} + 7x - 30 = 0$

$d = 49 + 120 = 169$

$x1 = \frac{ - 7 + 13}{2} = 3$

ОДЗ:

x+1>=0

x+6>=0

x>=-1

x>=-6

x€[-1;+беск)