Question

Find the zeros of the polynomial function.

f(x) = x3 + 5x2 - 4x - 20


x = -5, x = -2, x = 2

x = -2, x = 2

x = -5, x = 4

x = 5, x = -2, x = 2

Answer 1

f(x) = x^3 + 5x^2 - 4x - 20

The zeros of the polynomial function: x^3 + 5x^2 - 4x - 20 = 0

x^3 + 5x^2 - 4x - 20 = 0

x^2(x + 5) - 4(x + 5) = 0

(x^2 - 4)(x + 5) = 0

(x + 2)(x - 2)(x + 5) = 0

(x + 2) = 0; x = -2

(x - 2) = 0; x = 2

(x + 5) = 0; x = -5

Answer is the first one

x = -5, x = -2, x = 2