如图,乐器上的一根弦AB=80cm,两个端点A、B固定在乐器板面上,支撑点C是靠近点B的黄金分割点(即AC是AB与BC的比例中项),支撑点D是靠近点A的黄金分割点,则AC= cm;DC= cm。 答案:解析:由题意得:则AC=BD=AB=80×=40-40;AD=AB-BD=80-(40-40)=120-40;DC=AB-2AD=80-160.故本题答案为:40-40,80-160.— I'll go to Beijing for the coming summer holiday.— . A. Thank you B. It doesn't matter C. The same to you D. Have a good time