A piece of wire which is 24m long is cut into 2 parts[ ( 24-x) m & x m ]. They are bent to form squares .Let A m2 be the total area of the squares formed
a)Express A in terms of x
b)Find the minmum value of A
一條數學題(Function and graph)
2010-12-31 11:54 pm
回答 (2)
2011-01-01 12:12 am
✔ 最佳答案
(a) A=[(24-x)/4]^2+(x/4)^2A=(6- x/4)^2+(x/4)^2
A=36-3x+x^2/16+x^2/16
A=x^2/8 -3x +36
(b) A=x^2/8 -3x +36
=1/8 (x^2-24x) +36
=1/8 [(x-12)^2-144] +36
=1/8 (x-12)^2 +18
The minimum value of A=18 (m2)
2010-12-31 16:22:01 補充：
樓上解錯題??
2011-01-01 12:23 am
睇唔到個square==
收錄日期: 2021-04-19 23:48:49
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https://hk.answers.yahoo.com/question/index?qid=20101231000051KK00880