$\displaystyle {x}^{{-{{n}}}}=\frac{{1}}{{x}^{{n}}}$     and     $\displaystyle \frac{{1}}{{x}^{{-{{n}}}}}={x}^{{n}}$

You can eliminate negative exponents by rewriting the expression as 1, divided by the variable or number raised to the related positive exponent.

The Fraction Raised to a Negative Exponent Rule

When you have a fraction raised to a negative exponent, you can simply replace it with the reciprocal of the fraction to a positive exponent.

$\displaystyle {\left(\frac{{a}}{{b}}\right)}^{{-{{n}}}}={\left(\frac{{b}}{{a}}\right)}^{{n}}$