Монгол Бодлогын Сан

$\cos 3x+\sin2x\cos x+\sin x\cos 2x>-\sqrt{\dfrac{3}{2}}$ $(\alpha=\dfrac{\pi}{\fbox{a}}$ туслах өнцөг оруулбал) $\Leftrightarrow \sin(3x+\alpha)>-\dfrac{\sqrt{\fbox{c}}}{\fbox{b}} \Leftrightarrow x\in \left]-\dfrac{\fbox{d}}{36}\pi+\dfrac23\pi k;\dfrac{13}{36}\pi+\dfrac23\pi k\right[ (k\in \mathbb Z).$