Work Step by Step
Factor out $9x$ to obtain: $=9x(x^2-1) \\=x(x^2-1^2)$ Factor the difference of two squares using the formula $a^2-b^2=(a-b)(a+b)$ where $a=x$ and $b=1$ to obtain: $=9x(x-1)(x+1)$
You can help us out by revising, improving and updating this answer.Update this answer
After you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.