根据公式：sinαsinβ=[cos（α-β）- cos（α+β）]/2y=sin(x-π\3)sinx=[cos(π\3)-cos(2x-π\3)]/2=[1/2-cos(2x-π\3)]/2=1/4 -(1/2)cos(2x-π\3)∵-1≤cos(2x-π\3)≤1∴-1≤-cos(2x-π\3)≤1∴-1/4≤1/4-(1/2)c...