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