Question

x2+11-12=0
x2+x-56=0
помогите решить пожалуйста

Answer 1

Ответ:

Объяснение:

1)

$x^{2} + 11x - 12 = 0\\ D = 11^{2} + 12 * 4 = 121 + 48 = 169 = 13^{2} \\ x_{1} = \frac{-11 + 13}{2} = 2/2 = 1\\\\ x_{2} = \frac{-11 - 13}{2} = (-24)/2 = -12$

2)

$x^{2} +x - 56 = 0\\ D = 1^{2} + 56 * 4 = 224 + 1 = 225 = 15^{2} \\ x_{1} = \frac{-1 + 15}{2} = 14/2 = 7\\ \\ x_{2} = \frac{-1 - 15}{2} = (-16)/2= -8$