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2008-03-11 1:05 am
回答 (2)
2008-03-11 1:24 am
✔ 最佳答案
Given that y = sin x - 1 / 2, first sub y = 0
sin x = 1 / 2
x = pi / 6 or 5pi / 6
From the graph, you know that A ( 5pi / 6, 0 )
The height of AB:
0 - [ sin ( 3pi / 2 ) - 1/2 ]
= 3 / 2
Therefore the area of ABCD:
( 2pi - 5pi / 6 )( 3 / 2 )
= 7pi / 4 sqr. units
參考: My Maths Knowledge
2008-03-15 7:36 pm
The area of ABCD = 7pi / 4 sqr. units
收錄日期: 2021-04-23 20:32:32
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20080310000051KK01512