1) 6sin(2x-pi/6)cos(3x+pi/3)-3sin(5x+pi/6)=3(sin(2x-pi/6-3x-pi/3)+sin(2x-pi/6+3x+pi/3))-3sin(5x+pi/6)=3sin(-x-pi/2)+3sin(5x+pi/6)-3sin(5x+pi/6)=-3cosx
2) -1/2*cos3x-1/2*cos5x-√3/4+1/2*cos3x=0
-1/2*cos5x=√3/4
cos5x=-√3/2
5x=±arccos(-√3/2)+2pik
5x=±5pi/6+2pik
x=±pi/6+2pik/5, k∈Z