1) (x-1)x(x+1)(x+2)=24 2) (x+4)(x+5)(x+7)(x+8)=4 3) (x+1)(x+2)(x+3)(x+4)=120 это биквадратные

(x + 1)(x + 2)(x + 3)(x + 4) = 120
(x + 1)(x + 4)(x + 2)(x + 3) = 120
(x² + 5x + 4)(x² + 5x + 6) = 120
x² + 5x = a
(a + 4)(a + 6) = 120
a² + 10a + 24 = 120
a² + 10a - 96 = 0
a1 + a2 = -10
a1a2 = -96
a1 = -16
a2 = 6
x² + 5x = -16
x² + 5x + 16 = 0
x ∈ ∅
x² + 5x = 6
x² + 5x - 6 = 0
x1 = -1
x2 = 6