Answer
$2(1-2x)(1+2x)$
Work Step by Step
Factor out $2$ to obtain:
$=2(1-4x^2)
\\=2[1^2-(2x)^2]$
RECALL:
$a^2-b^2=(a-b)(a+b)$
Use the formula above with $a=1$ and $b=2x$ to factor the binomial and obtain:
$=2(1-2x)(1+2x)$