Chapter P, Prerequisites - Section P.3 - Integer Exponents and Scientific Notation - P.3 Exercises - Page 23: 33

(a) $\frac{b^{3}}{3a}$ (b) $\frac{s^{3}}{q^{7}r^{4}}$

a) $(\frac{3a}{b^{3}})^{-1}$ $=\frac{b^{3}}{3a}$ b) $(\frac{q^{-1}r^{-1}s^{-2}}{r^{-5}sq^{-8}})^{-1}$ $=\frac{r^{-5}sq^{-8}}{q^{-1}r^{-1}s^{-2}}$ $=\frac{s^{3}}{q^{7}r^{4}}$