Answer
$\dfrac{16}{x^2}$
Work Step by Step
Using the laws of exponents, the given expression, $
\dfrac{(4x^3)^2}{x^8}
,$ simplifies to
\begin{array}{l}\require{cancel}
\dfrac{4^{1(2)}x^{3(2)}}{x^8}
\\\\=
\dfrac{4^{2}x^{6}}{x^8}
\\\\=
16x^{6-8}
\\\\=
16x^{-2}
\\\\=
\dfrac{16}{x^2}
.\end{array}
