空間中ABCD四點, AB = 1, BC = 2, CD = 3, 角ABC = 角BCD =120度,
求AD =?
收錄日期: 2021-04-24 23:25:24
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20141229000015KK00037