Answer:
yes
Step-by-step explanation:
The other factor is (x+5), so the product is ...
(x^4 -1)(x +5) = x^5 +5x^4 -x -5 = P(x)
(x^4 -1) is a factor of P(x).
_____
It is not a primitive factor, because it can be factored as ...
x^4 -1 = (x^2 -1)(x^2 +1) = (x -1)(x +1)(x^2 +1)
The complete factorization of P(x) to real numbers is ...
P(x) = (x -1)(x +1)(x +5)(x^2 +1)
