The two values of listed in the table whose outputs are zero are roots of , defined as . In other words, those values of (-1 and 2) satisfies the condition that .
b)<em> What is the multiplicity of each zero?</em>
From the Fundamental Theorem of Algebra, we know that third-order polynomials have three roots and from we understand that those two known zeroes with a multiplicity of 1, since there is a third root within , where and .