[tex]\bf \left.\qquad \qquad \right.\textit{negative exponents}\\\\
a^{-{ n}} \implies \cfrac{1}{a^{ n}}
\qquad \qquad
\cfrac{1}{a^{ n}}\implies a^{-{ n}}
\qquad \qquad
a^{{{ n}}}\implies \cfrac{1}{a^{-{{ n}}}}\\\\
-------------------------------\\\\
\cfrac{f^{-2}}{5a}\quad
\begin{cases}
a=1\\
f=\frac{1}{3}
\end{cases}\implies \cfrac{\left( \frac{1}{3} \right)^{-2}}{5(1)}\implies \cfrac{\left( \frac{3}{1} \right)^{2}}{5(1)}\implies \cfrac{\frac{3^2}{1^2}}{5}\implies \cfrac{9}{5}[/tex]
