Question

-8sin(3п/7) / cos(п/14)
Решите пожалуйста!

Answer 1

sin(3π/7)=sin(6π/14)=sin(7π/14-π/14)=sin(π/2-π/14)
По формуле приведения
sin(π/2-π/14)=cos(π/14)
Тогда
-8 sin(3π/7)/cos(π/14)=-8 cos(π/14)/cos(π/14)=-8
Ответ: -8