[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}}}}
\\\\
-------------------------------\\\\
(7^3)^{-2}\implies 7^{-2\cdot 3}\implies 7^{-6}\implies \cfrac{1}{7^6}\implies \cfrac{1}{7\cdot 7\cdot 7\cdot 7\cdot 7\cdot 7}[/tex]
