Sin П/18 * cos П/9 + sin П/9 * cos П/18 / sin П/36 * cos 35П/18 + sin 35П/18 * cos П/36 =

Question

Sin П/18 * cos П/9 + sin П/9 * cos П/18
/ sin П/36 * cos 35П/18 + sin 35П/18 * cos П/36 =

Answer 1

1)=sin(π/18+π/9)=sinπ/6=1/2
2)=sin(π/36+35π/18)=sin71π/36=sin(2π-π/36)=-sinπ/36