Сократите дробь: (20+10a+5a^2)/(a^3-8).

\[\frac{20 + 10a + 5a^{2}}{a^{3} - 8} =\]

\[= \frac{5 \cdot \left( 4 + 2a + a^{2} \right)}{a^{3} - 8} =\]

\[= \frac{5 \cdot \left( 4 + 2a + a^{2} \right)}{(a - 2)\left( a^{2} + 2a + 4 \right)} =\]

\[= \frac{5}{a - 2}\]