f(x)=sin(x+ π/6) +sin(x-π/6) +acosx +b(a,b∈r,且均为常数）=2sinxcosπ/6+acosx+b=√3sinx+acosx+b=√(3+a^2)sin(x+θ)+b (sinθ=a/√(3+a^2),cosθ=√3/√(3+a^2),f（x)在区间[-π/3,0]上单调递增,且恰好能够...