回複：你可以證明所有的三角形都是等腰三角形嗎？

來源: 於 2009-01-31 12:35:06 [舊帖] [給我悄悄話] 本文已被閱讀：次

Point O (the cross point of AO and A'O) is either overlap with A' (when AB=BC) or outside of triangle ABC.