Respuesta :

(m^2 - 4)(m^2 + 1) = 0

(m - 2)(m + 2)(m^2 + 1) = 0

(m - 2)= 0  gives m = 2
(m + 2)= 0 gives m = -2
m^2 + 1 = 0
m^2 = -1
 m = i, -i

The zeros are    -2, 2 , i, -i