Упростите выражение: -11a^3 √(49/a^6 );где a<0.

\[- 11a^{3}\sqrt{\frac{49}{a^{6}}};где\ a < 0\]

\[- 11a^{3}\sqrt{\frac{49}{a^{6}}} = - 11a^{3} \cdot \frac{7}{\left| a^{3} \right|} =\]

\[= \frac{- 11a^{3} \cdot 7}{- a^{3}} = 77.\]