Question

Select all of the roots of x3 + 2x2 – 16x– 32.

Answer 1

Answer:

x^3+2x^2-16x-32

= x^2(x+2) - 16(x+2)

= (x+2)(x^2-16)

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

as x^2-16 = x^2 - 4^2

so we have roots

-2, -4 and 4