\[\left( a^{3} - 2 \right)\left( a^{3} + 2 \right) - \left( a^{3} + 3 \right)^{2} =\]
\[= - 6a^{3} - 13\]
\[при\ a = - 2:\ \ \ \ \ \ \ \ \ \ \]
\[6 \cdot 8 - 13 = 35.\ \ \]