[tex]sin3x \leq \frac{ \sqrt{2} }{2} \\ cos \frac{x}{2} \geq \frac{1}{2} \\ sin(x- \frac{ \pi }{4} ) \geq \frac{ \sqrt{3} }{2} \\ cos(2x+ \frac{ \pi }{6} ) \leq - \frac{1}{2} [/tex]