Question

решите уравнение:

x^3+2x^2-4x-8=0

Answer 1

x^3+2x^2-4x-8=0

x^2 (x+2) - 4(x+2) = 0

(x+2) ( x^2 - 4) = 0

x+2 = 0   i    x^2 -4 = 0

x=-2        i    x^2 = 4   / "V

                      x = +2 i x = - 2