sederhanakanlah (a⁴×b^negatif ³)^ 7?

[tex]$ \begin{align} \display (a^4 \ x \ b^{-3})^7 &= (a^4)^7 \ x \ (b^{-3})^7 \\ &= a^{28}b^{-21} \\ &= \frac{a^{28}}{b^{21}} \end{align}[/tex]