Question

$( 81a^{-8}) ^{ -frac{3}{4} }$

Answer 1

$(81a^{-8})^{-frac{3}{4}}=(3^4cdot a^{-8})^{-frac{3}{4}}=(3^4)^{-frac{3}{4}}cdot(a^{-8})^{-frac{3}{4}}=3^{-3}cdot a^6= frac{a^6}{3^{-3}} = frac{a^6}{27}$