Answer
$(1-3x)(1+3x)(1+9x^2)$
Work Step by Step
The given binomial can be written as:
$=1^2-(9x^2)^2$
The binomial is a difference of two squares.
RECALL:
$a^2-b^2=(a-b)(a+b)$
Factor the difference of two squares using the formula above with $a=1$ and $b=9x^2$ to obtain:
$=(1-9x^2)(1+9x^2)
\\=[1^2-(3x)^2)](1+9x^2)$
The first factor is a difference of two squares. Factor using the formula above with $a=1$ and $b=3x$ to obtain:
$=(1-3x)(1+3x)(1+9x^2)$