Answer:
[tex] {(a - 2b)}^{3} \\ {( (- 2) - 2 - \frac{1}{2}) }^{3} \\ {( \frac{ - 2(2) - 2(2) - 1}{2}) }^{3} \\ {( \frac{ - 4 - 4 - 1}{2}) }^{3} \\ {( \frac{ - 9}{2} )}^{3} \\ ( - \frac{9}{2} ) \times ( - \frac{9}{2} ) \times( - \frac{9}{2} ) \\ - \frac{729}{8} \\ - 91 \frac{1}{8} \\ [/tex]
