# 1.
(x^2 - 1)^2 + (x^2 - 6x - 7)^2 = 0
(x - 1)^2 *(x + 1)^2 + (x - 7)^2*(x + 1)^2 = 0
(x + 1)^2(x^2 - 2x +1 + x^2 - 14x + 49) = 0
(x +1)^2 (2x^2 - 16x + 50) = 0
1) (x + 1)^2 = 0
x + 1 = 0
x = - 1
2) 2x^2 - 16x + 50 = 0 /:2
x^2 - 8x + 25 = 0
D = 64 - 100 = - 36 < 0
корней на множестве действительных чисел нет
Ответ
- 1
================================
# 2.
x^3 + 3x^2 - x - 3 = 0
x^2 (x + 3) - 1(x + 3) = 0
(x^2 - 1)(x + 3) = 0
1) x^2 - 1 = 0
x₁ = - 1
x₂ = 1
2) x + 3 = 0
x₃ = - 3
Ответ
- 3; - 1; 1