[tex] \bf ~~~~~~~~~~~~\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}} \\\\[-0.35em] \rule{34em}{0.25pt}\\\\ \left( \cfrac{36b^3}{9a^5} \right)^3\implies \left( \cfrac{4b^3}{a^5} \right)^3\implies \stackrel{\textit{distributing the exponent}}{\left(\cfrac{4^3b^{3\cdot 3}}{a^{5\cdot 3}}\right)}\implies \cfrac{64b^9}{a^{15}} [/tex]