[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}}
\\\\
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\cfrac{3x^2}{xy}\cdot \cfrac{4xy^2}{\frac{1}{y}}\implies \cfrac{3x^2}{xy}\cdot \cfrac{4xy^2}{y^{-1}}\implies \cfrac{3x^2x^1y^2}{xy^1y^{-1}}\implies \cfrac{3x^{2+1}y^2}{xy^{1-1}}
\\\\\\
\cfrac{3x^3y^2}{xy^0}\implies \cfrac{3x^3y^2}{x^1}\implies 3x^3y^2x^{-1}\implies 3x^{3-1}y^2\implies 3x^2y^2[/tex]
