A.19km
B.20km
C.21km
D.22km
更新1:
怎樣計????有無詳細d.........是c or d 呀? 有無人知
有條數學唔識做....有無人識做呀?
2007-12-05 12:37 am
1. A ship sails for 10km in the direction N70∘E from post A to post B. The it sails for 20km towards south to port C. C is due south of B. Find the distance between port A and port C.
A.19km
B.20km
C.21km
D.22km
A.19km
B.20km
C.21km
D.22km
回答 (4)
2007-12-05 1:40 am
✔ 最佳答案
AB = 10kmBC = 20km
B is N70*E of A.
C is south of B.
angle ABC = 70*
By cosine law,
AC^2 = AB^2 + BC^2 - 2(AB)(BC)cos70*
AC = 19.06km
Ans. A
2007-12-05 1:16 am
About ｃ。因為係關於N70。
2007-12-05 1:05 am
About D
收錄日期: 2021-04-24 07:54:54
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https://hk.answers.yahoo.com/question/index?qid=20071204000051KK01534