Question

What is a cubic polynomial function in standard form with zeros -5, 1, and 3?

Answer 1

FIRST, find the factors:
x = -5 --> (x + 5) = 0
x = 1 --> (x - 1) = 0
x = 3 --> (x - 3) = 0

NEXT, multiply all the factors:
(x + 5) (x - 1) (x - 3) = 0
--> x³ + x² - 17x + 15 = 0
--> f(x) = x³ + x² - 17x + 15    or    y = x³ + x² - 17x + 15