f(x)=sin³xcosx+cos³xsinx+√3 sin²x
=sinxcosx(sin²x+cos²x)+√3 (1-cos2x)/2
=½ sin2x - √3 /2 cos2x + √3 /2
=sin(2x-π/3) + √3 /2
f(x) 的递减区间是 2x-π/3∈[π/2+kπ,3π/2+kπ] (k∈Z)
即 x∈[5π/12+kπ/2,11π/12+kπ/2] (k∈Z)
在 0≤x≤π 内的单调递减区间是 x∈[5π/12,11π/12]
值域是 [√3 /2 - 1,√3 /2 + 1]