[tex]x^{\frac{1}{\frac{-3}{6} }}[/tex]
First, let's deal with the fraction in the denominator of the exponent. Multiply the top and bottom of the exponent by 6.
[tex]x^{\frac{6}{-3} }[/tex]
Now that the fraction in the denominator is taken care of, we can reduce the denominator.
[tex]x^{-2}[/tex]. Some professors might accept this as simplest form, but others might ask you to get rid of the negative.
[tex]x^{-2} = \frac{1}{x^{2} }[/tex]
