Chapter 5 - Section 5.2 - Negative Exponents and Scientific Notation - Exercise Set - Page 354: 61

$\Big(\dfrac{a^{-5}b}{ab^{3}}\Big)^{-4}=a^{24}b^{8}$

$\Big(\dfrac{a^{-5}b}{ab^{3}}\Big)^{-4}$ Evaluate the exponential expression: $\Big(\dfrac{a^{-5}b}{ab^{3}}\Big)^{-4}=\dfrac{a^{20}b^{-4}}{a^{-4}b^{-12}}=...$ Now, evaluate the division and simplify: $...=a^{20-(-4)}b^{-4-(-12)}=a^{24}b^{8}$