As follows:
圖片參考：http://f.imagehost.org/0957/ScreenHunter_04_Jan_23_19_01.gif
maths~~~~~~
2010-01-24 7:39 am
回答 (1)
2010-01-24 7:55 am
✔ 最佳答案
By the above result , A1A2/OA1=sqrt3 => A3OA4=60 ,
A2A3/OA2=sqrt3 => A3OA2=60
A2A1/A1O=sqrt3 => A2OA1=60
OA1=OA2*tan60=(OA3*tan60)*tan60=(OA4*tan60)*tan60*tan60=OA4(tan60)^3
=>OA1=OA4(sqrt3)^4=OA4(3sqrt3)
=>OA4=OA1/(3sqrt3)=1/(3sqrt3)=sqrt3/9//
2010-01-23 23:56:01 補充：
打錯
2010-01-23 23:57:36 補充：
OA1=OA2*cos60=(OA3*cos60)*tan60=(OA4*cos60)*tan60*cos60=OA4(cos60)^3
=>OA1=OA4(1/2)^3=OA4(1/8)
=>OA4=OA1*(8)=8//
收錄日期: 2021-04-23 20:46:11
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20100123000051KK01869