Решите тригонометрические неравенства.(c помощью единичной окружности)
а)[tex]cos \frac{2x}{3} \ \textless \ - \frac{ \sqrt{2} }{2} [/tex]
б)[tex]2sin \frac{x}{4} cos \frac{x}{4} \ \textgreater \ - \frac{1}{2} [/tex]
а)[tex]cos \frac{2x}{3} \ \textless \ - \frac{ \sqrt{2} }{2} [/tex]
б)[tex]2sin \frac{x}{4} cos \frac{x}{4} \ \textgreater \ - \frac{1}{2} [/tex]
Answers & Comments
Verified answer
1)3π/4+2πn<2x/3<5π/4+2πn9π/8+3πn<x<15π/8+3πn
2)2sinx/4*cosx/4=sinx/2>-1/2
-π/6+2πn<x/2<7π/6+2πn
-π/3+4πn<x<7π/3+4πn