Answer:
One possible polynomial is given by:

Explanation:
Zeros of a function:
Given a polynomial f(x), this polynomial has roots
such that it can be written as:
, in which a is the leading coefficient.
Single root at 0, double root at 3:
This means that:

Decreases as x approaches infinity.
This means that the leading coefficient should be negative. I am going to use -1. So
