y=cos(x/2)+sin(60-x/2)=cos(x/2)+sin60cos(x/2)-cos60sin(x/2)=[(2+√3)/2]cos(x/2)-(1/2)sin(x/2)=√{[(2+√3)/2]^2+(1/2)^2}sin(a-x/2)=√[(7+4√3)/4+1/4]sin(a-x/2)=√(2+√3)sin(a-x/2)其中,tana=[(2+√3)/2]/...