\[1)\ Производная\ отрицательна:\]
\[= 8\sin^{2}x + 8\cos^{2}x + 40 =\]
\[= 8 + 40 = 48\]
\[b = \frac{\left( 4\sin x - 8 \right) \pm \sqrt{48}}{2 \bullet 2} =\]
\[= \frac{4\sin x - 8 \pm 4\sqrt{3}}{4} =\]
\[= \sin x - 2 \pm \sqrt{3}\]
\[b < \sin x - 2 - \sqrt{3};\]
\[b > \sin x - 2 + \sqrt{3}.\]
\[2)\ Не\ зависит\ от\ x:\]
\[b < - 1 - 2 - \sqrt{3}\]
\[b < - 3 - \sqrt{3}.\text{\ \ }\]
\[b > 1 - 2 + \sqrt{3}\]
\[b > \sqrt{3} - 1.\]
\[Ответ:\ \ \]
\[b \in \left( - \infty;\ - 3 - \sqrt{3} \right) \cup \left( \sqrt{3} - 1;\ + \infty \right).\]