Question

A polynomial function has a zero at x = 3. Which of the following expressions must be one factor of the polynomial?

Answer 1

You can write a polynomial with zeros \(z_1,z_2,...,z_n\) as
\[P(x) = a(x-z_1)(x-z_2)...(x-z_n)\]where \(a\) is a constant used to make the polynomial pass through a give point, or 1.