Paul's Online Notes
Paul's Online Notes
Home / Algebra / Polynomial Functions / Zeroes/Roots of Polynomials
Show Mobile Notice Show All Notes Hide All Notes
Mobile Notice
You appear to be on a device with a "narrow" screen width (i.e. you are probably on a mobile phone). Due to the nature of the mathematics on this site it is best viewed in landscape mode. If your device is not in landscape mode many of the equations will run off the side of your device (you should be able to scroll/swipe to see them) and some of the menu items will be cut off due to the narrow screen width.

Section 5.2 : Zeroes/Roots of Polynomials

2. List all of the zeros of the following polynomial and give their multiplicities.

\[g\left( x \right) = {x^6} - 3{x^5} - 6{x^4} + 10{x^3} + 21{x^2} + 9x = x{\left( {x - 3} \right)^2}{\left( {x + 1} \right)^3}\]

Show All Steps Hide All Steps

Start Solution

For this problem the polynomial has already been factored and so all we need to do is get the zeroes/roots from the factored form.

The zeroes/roots of this polynomial are : \(x = 0\), \(x = 3\) and \(x = - 1\).

Show Step 2

For the multiplicities just remember that the multiplicity of the zero/root is simply the exponent on the term that produces the zero/root. Therefore, the multiplicities of each zero/root is,

\[\begin{align*}& x = 0:{\mbox{ multiplicity 1}}\\ & x = 3:{\mbox{ multiplicity 2}}\\ & x = - 1:{\mbox{ multiplicity 3}}\end{align*}\]