How do you write a polynomial with zeros 1,-4,5 and leading coefficient 1?

1 Answer
Oct 15, 2016

The equation is y = x^3 - 2x^2 - 19x + 20

Explanation:

A polynomial in factored form, is written as y = a(x - a)(x - b)(x- c)... where a, b, c, ... are the zeroes and a is the leading coefficient.

Hence, we can write the polynomial function as

y = 1(x - 1)(x + 4)(x - 5)

If you want this in standard form, simply multiply out.

y = 1(x^2 + 3x - 4)(x - 5)

y = x^3 + 3x^2 - 4x - 5x^2 - 15x + 20

y = x^3 - 2x^2 - 19x + 20

Hopefully this helps!