不懂part c
求步驟
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F5 數學一條問題3
2012-11-02 8:04 am
回答 (1)
2012-11-02 9:03 am
✔ 最佳答案
(c)(BC : (AD= ∠CAB : ∠ABD= 30° : (∠ABC - ∠CBD)∵ (AB : (CD = 3 : 3 , i.e. (AB = (CD
∴ ∠ADB = ∠CBD = 30° : (∠ABC - ∠ADB)= 30° : (105° - 45°) ...... (由 (a) 及 (b) 的結果) = 30° : 60°= 1 : 2
2012-11-02 01:05:26 補充：
(AB = (CD
∴∠ADB = ∠CBD (等弧對等角)
收錄日期: 2021-04-16 15:17:12
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20121102000051KK00003