Ответ:
При \(c=-3\): \[\frac{c^2+3c+7}{c^3-8}+\frac{c+3}{8-c^3}=\frac{9-9+7}{-27-8}+\frac{-3+3}{8-(-27)}.\]
\[=\frac{7}{-35}+\frac{0}{35}=-\frac{1}{5}.\]
Ответ: \(-\frac{1}{5}\).
При \(c=-3\): \[\frac{c^2+3c+7}{c^3-8}+\frac{c+3}{8-c^3}=\frac{9-9+7}{-27-8}+\frac{-3+3}{8-(-27)}.\]
\[=\frac{7}{-35}+\frac{0}{35}=-\frac{1}{5}.\]
Ответ: \(-\frac{1}{5}\).