maths
2010-09-06 1:08 am
回答 (1)
2010-09-06 1:17 am
✔ 最佳答案
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Let BC=AD=x m and CD=y m
BC+CD+AD=200=>2x+y=200...(*)
The area
=xy
=x(200-2x)
=-2x^2+200x
=-2(x^2-100x)
=-2(x^2-100x+50^2-50^2)
=-2(x-50)^2+5000
So, when x=50, the area is maximized.
Hence, the dimension is 100m*50m
收錄日期: 2021-04-22 00:51:36
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20100905000051KK01064