名校
1 . “精准扶贫,修路先行”,为解决城市A和山区B的物流运输问题,方便B地的农产品运输到城市A交易,计划在铁路AD间的某一点C处修建一条笔直的公路到达B地.示意图如图所示,
千米,
千米,
.已知农产品的铁路运费为每千米1百元,公路运费为每千米2百元,农产品从B到A的总运费为
百元.为了求总运费
的最小值,现提供两种方案建立函数关系,方案1:设
千米;方案2:设
.
![](https://img.xkw.com/dksih/QBM/2021/5/25/2728844525436928/2763381872025600/STEM/da1dff13-1d5e-4a97-bcfc-47660ced5353.png?resizew=203)
(1)试将
分别表示为关于
、
的函数关系式
和
;
(2)请只选择一种方案,求出总运费
的最小值以及此时
的长度.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80739f2486099ffd39a3038c60f41825.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/00eadc41339daa56623a3d3d28460936.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ff83a75900ae3d07bbb4eda227b449cd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/88bfc0387785bf3c60f75ed3d34cc98a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e1950345548fe750b80ce79b168969ca.png)
![](https://img.xkw.com/dksih/QBM/2021/5/25/2728844525436928/2763381872025600/STEM/da1dff13-1d5e-4a97-bcfc-47660ced5353.png?resizew=203)
(1)试将
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c24095e409b025db711f14be783a406c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/51c530f4b7491b95acb8ce3eef9aa09d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3634f1a6094deeafc4c3de8277d85ce6.png)
(2)请只选择一种方案,求出总运费
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
您最近一年使用:0次
2021-07-13更新
|
534次组卷
|
4卷引用:湖北省黄石市第二中学2023-2024学年高二上学期第三次统测数学试题
19-20高二下·江苏苏州·期中
名校
解题方法
2 . 如图所示,某镇有一块空地
,其中
.当地政府计划将这块空地改造成一个旅游景点,拟在中间挖一个人工湖
,其中
都在边
上,且
,挖出的泥土堆放在
地带上形成假山,剩下的
地带开设儿童游乐场.为安全起见,需在
的周围安装防护网.设
.
![](https://img.xkw.com/dksih/QBM/2021/3/11/2675705267904512/2676338543640576/STEM/a3df37ce-ea14-4944-80d0-5973eac8a189.png)
(1)当
时,求
的值,并求此时防护网的总长度;
(2)若
,问此时人工湖用地
的面积是堆假山用地
的面积的多少倍?
(3)为节省投入资金,人工湖
的面积要尽可能小,问如何设计施工方案,可使
的面积最小?最小面积是多少?
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3fe95f656b98b53f71a9d72bf0c9a4b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6748adca7118689bffd79ce7666c90b4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/25dd698d57d1cf239eb8752aecaaa4f4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7789a500686c7a73770404ead6af0590.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/51c3fe26b378cb2665c06c5d8039d675.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0edafce95aade0386bc0d78f679dcf47.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/caf2b5e712b42f748a3c30bb5d160c18.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1c29e963e1871b415c086bc600d16bd5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0fb35158a52a23a6e57ff890cef8c7cf.png)
![](https://img.xkw.com/dksih/QBM/2021/3/11/2675705267904512/2676338543640576/STEM/a3df37ce-ea14-4944-80d0-5973eac8a189.png)
(1)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bc8a5801b87418e955e5d8b5f785b090.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c24095e409b025db711f14be783a406c.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c9f94c98de139b7455211d96df0a668.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/25dd698d57d1cf239eb8752aecaaa4f4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0edafce95aade0386bc0d78f679dcf47.png)
(3)为节省投入资金,人工湖
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/25dd698d57d1cf239eb8752aecaaa4f4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/25dd698d57d1cf239eb8752aecaaa4f4.png)
您最近一年使用:0次
2021-03-12更新
|
1205次组卷
|
7卷引用:江苏省苏州中学园区校2019-2020学年高二下学期期中数学试题