Question

Решить уравнение x3 – 4x2 – 9x + 36 = 0

Answer 1

$x^3 - 4x^2 - 9x + 36 = 0 \ x^2(x-4)-9(x-4) = 0 \ (x^2-9)(x-4) = 0 \ (x-3)(x+3)(x-4)=0; => \ x_1=3; x_2=-3; x_3=4$