Question

Решите уравнение: x2-14x+36=0​

Answer 1

Ответ:

$x1 = 7 + \sqrt{13}$

$x2 = 7 - \sqrt{13}$

Объяснение:

${x}^{2} - 14x + 36 = 0$

$d = {b}^{2} - 4ac = { ( - 14)}^{2} - 4 \times 1 \times 36 = 196 - 144 = 52$

$x1 = \frac{ - b + \sqrt{d} }{2a} = \frac{ - ( - 14) + \sqrt{52} }{ 2 \times 1} = \frac{14 + \sqrt{52} }{2} = \frac{14 + 2\sqrt{13} }{2} = 7 + \sqrt{13}$

$x2 = \frac{ - b - \sqrt{d} }{2a} = \frac{ - ( - 14) - \sqrt{52} }{2 \times 1} = \frac{14 - \sqrt{52} }{2} = \frac{14 - 2 \sqrt{13} }{2} = 7 - \sqrt{13}$