$$\left(2a\right)^{-1} \cdot \left(\frac{b}{2}\right)^{-3} \cdot \left(a \cdot b\right)^3$$

Vi skriver om ved å bruke at $x^{-n} = \dfrac{1}{x^n}$ og $\left(\dfrac{p}{q}\right)^{-n} = \left(\dfrac{q}{p}\right)^n$:

$$= \frac{1}{2a} \cdot \left(\frac{2}{b}\right)^{3} \cdot a^3 b^3$$ $$= \frac{1}{2a} \cdot \frac{8}{b^3} \cdot a^3 b^3$$ $$= \frac{8 \cdot a^3 \cdot b^3}{2a \cdot b^3}$$ $$= \frac{8a^3}{2a}$$ $$= 4a^2$$