Respuesta :

Answer:

k = 3.

Step-by-step explanation:

By the Factor Theorem. if x+a is a factor of f(x)  then f(-a) = 0.

Here we use f(-1):

f(-1) = (-1)^3 + 2(-1) + k = 0

-1 - 2 + k = 0

k = 3.