f(x)=√3sinxcosx+cos²x+a =(sin2x)×(√3/2)+(cos2x+1)×(1/2)+a=(cosπ/6)×sin2x+(sinπ/6)×cos2x+1/2+a=sin(2x+π/6)＋(a+1/2)-π/6≤x≤π/3时-π/6≤2x+π/6≤5π/6即,-1/2≤sin(2x+π/6)≤1所以,a≤f(x...