Question

Помогите решить неравенство

Спасибо

Answer 1

       Замена  $x=6t$  
     
   $\frac{sint}{cos2t*cos3t} \ \textgreater \ 0 \\ \left \{ {{ sint \ \textgreater \ 0} \atop { cos2t \ \textgreater \ 0 , cos3t\ \textgreater \ 0}} \right.\\ \left \{ {{ sint \ \textgreater \ 0} \atop { cos2t \ \textless \ 0 , cos3t\ \textless \ 0}} \right.\\ \left \{ {{ sint \ \textless \ 0} \atop { cos2t \ \textless \ 0 , cos3t\ \textgreater \ 0}} \right. \\ \left \{ {{ sint \ \textless \ 0} \atop { cos2t \ \textgreater \ 0 , cos3t\ \textless \ 0}} \right.$ 
    
  $t \in (2\pi*n-\pi ; \frac{12\pi*n-5\pi}{6} ) \\ t \in (2\pi*n- \frac{3\pi}{4} ; \frac{4\pi*n-\pi}{2} ) \\ t \in (2\pi*n- \frac{\pi}{4} ; \frac{12\pi*n-\pi}{6} ) \\ t \in (2\pi*n; \frac{12\pi*n+\pi}{6} ) \\ t \in (2\pi*n + \frac{\pi}{4} ; \frac{4\pi*n+\pi}{2} ) \\ t \in (2\pi*n + \frac{3\pi}{4} ; \frac{12\pi*n+5\pi}{6} )$
 осталось заменить и поделить  на      $6$