Sin(4arccos(-0,5)-2arctg√3/3)

Question

Sin(4arccos(-0,5)-2arctg√3/3)

Answer 1

Sin(4*2*pi/3-2*pi/6)=sin(8*pi/3-pi/3)=sin(7*pi/3)=sin(2*pi+pi/3)=sin(pi/3)=v3/2