b/a=c/a,则b=c.又a²－b²=c(a－b),即(a－b)(a＋b－c)=0.①若a－b=0,则a=b=c,则bsinB/c=√3/2；②若a＋b－c=0,因b=c,则a=0,不成立.总之,bsinB/c=√3/2.