Answer
$\frac{1}{x^{3}}$
Work Step by Step
We know that $a^{−n}=\frac{1}{a^{n}}$ and $\frac{1}{a^{-n}}=a^{n}$ (as long as a is a nonzero real number and n is an integer).
Therefore, $\frac{x^{-4}}{x^{-1}}=\frac{1}{x^{4}}\times x=\frac{x}{x^{4}}=x^{1-4}=x^{-3}=\frac{1}{x^{3}}$.