Question

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

Answer 1

Polynomial is `(x-1)(x+4)(x-5)`
or `x^3-2x^2-19x+20`

Explanation:

A polynomial (say with `x` as variable) with zeros 1,-4, 5, means that when `x` is put equal to either `1` , `-4` or `5`, its value reduces to zero.

Hence the polynomial would be `(x-1)(x+4)(x-5)`

or `(x-1)(x^2+4x-5x-20)` (multiplying last two factors)

or `(x-1)(x^2-x-20)`

or `x^3-x^2-20x-x^2+x+20` or

`x^3-2x^2-19x+20`