What is the complete factorization of the polynomial below?

(x - 1)(x + 1)(x + 3).

Step-by-step explanation:

x^3 + 3x^2 - x - 3            Factor by grouping:

= x^2(x + 3) - 1(x + 3)       x+3 is common .

= (x^2 - 1)(x + 3)                x^2 - 1 is the difference of 2 squares.

= (x - 1)(x + 1)(x + 3).