f(x)=sin（x＋3兀／2)sin(x-2π） 求函数f(x)的最直和最小正周期 计算f(π/6）+f（π/12）

f(x) = sin(x+3π/2)sin(x-2π) = -cosxsinx = -1/2sin2x 最大值1/2 最小值-1/2 最小正周期2π/2=π f(π/6)=-1/2sinπ/3=-√3/4 f(π/12)=-1/2sinπ/6=-1/4 f(π/6)+f(π/6)=-(√3+1)/4