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請問點證明呀!!!!
圓形問題!!!!!pls
2007-08-16 8:55 pm
回答 (1)
2007-08-16 9:11 pm
✔ 最佳答案
2∠DBA=∠DOA(∠ at centre=2∠ at ⊙ce)2∠BDC=∠BOC(∠ at centre=2∠ at ⊙ce)
x+y=360-∠DOA-∠BOC(∠s at a pt.)
=360-2∠DBA-2∠BDC
=2(180-∠DBA-∠BDC)
=2θ(∠s sum of △)
參考: me
收錄日期: 2021-04-22 00:15:12
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20070816000051KK02033