Answer:
y = x³ - 3x² - x + 3
Step-by-step explanation:
Given the zeros x = - 1, x = 1 and x = 3 then
(x + 1), (x - 1) and (x - 3) are the factors and the polynomial is the product of the factors, hence
y = a(x - 1)(x + 1)(x - 3) ← a is a multiplier
let a = 1 and expand the factors
y = (x² - 1)(x - 3)
= x³ - x - 3x² + 3
= x³ - 3x² - x + 3 ← in standard form
