\[\boxed{\text{329\ (329).}\text{\ }\text{Еуроки\ -\ ДЗ\ без\ мороки}}\]
Пояснение.
Решение.
\[\textbf{а)}\ (x + 9)(x - 2)(x - 15) < 0\]
\[x \in ( - \infty;\ - 9) \cup (2;15).\]
\[\textbf{б)}\ x(x - 5)(x + 6) > 0\]
\[(x + 6)x(x - 5) > 0\]
\[x \in ( - 6;0) \cup (5;\ + \infty).\]
\[\textbf{в)}\ (x - 1)(x - 4)(x - 8)(x - 16) < 0\]
\[x \in (1;4) \cup (8;16)\text{.\ }\]