如图,某景区内有两条道路
、
,现计划在
上选择一点
,新建道路
,并把
所在的区域改造成绿化区域.已知
,
,
.若绿化区域
改造成本为
万元
,新建道路
成本为
万元
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/24/e07a0409-2806-43bb-99fe-ae32b4051e07.png?resizew=152)
(1)①设
,写出该计划所需总费用
的表达式,并写出
的范围;
②设
,写出该计划所需总费用
的表达式,并写出
的范围;
(2)从上面两个函数关系中任选一个,求点
在何处时改造计划的总费用最小.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/20a541b81584a032f571159ea152c85a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/20a541b81584a032f571159ea152c85a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/954d2fd2aecd31ff67d975bc8981023a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d96b98fa3d42c6110aacdd8b40cc878.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63f605387255af0470d97071f0d8b9bf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d07ae0b4264da6a8812454ffd2f20d94.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f73840c256b07fc8619ca3864ab6cda0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d07ae0b4264da6a8812454ffd2f20d94.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3c1feb40df85e8deb28601e2bfec896f.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/24/e07a0409-2806-43bb-99fe-ae32b4051e07.png?resizew=152)
(1)①设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/01dcbd171693a47c5b932a5e84de10c6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5d54a032e273b515ed2d0e0aebc2217e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c24095e409b025db711f14be783a406c.png)
②设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/88bfc0387785bf3c60f75ed3d34cc98a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/46be55c8f2760d6db125f46691a3de48.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
(2)从上面两个函数关系中任选一个,求点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
19-20高二下·江苏南京·期中 查看更多[2]
江苏省南京市南师附中2019-2020学年高二下学期期中数学试题(已下线)第五章 导数及其应用B卷(综合培优)-【双基双测】2021-2022学年高二数学同步单元AB卷(苏教版2019选择性必修第一册)
更新时间:2020-05-29 17:30:00
|
【知识点】 成本最小问题
相似题推荐
解答题-应用题
|
适中
(0.65)
名校
解题方法
【推荐1】某房地产开发商有一块如图(1)所示的四边形空地ABCD,经测量,边界CB与CD的长都为2km,所形成的角∠
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/1/299a0311-2f5e-4963-a78e-f3492663db00.png?resizew=232)
(I)如果边界AD与AB所形成的角
,现欲将该地块用固定高度的板材围成一个封闭的施工场地,求至多购买多少千米长度的板材;
(II)当边界AD与CD垂直,AB与BC垂直时,为后期开发方便,拟在这块空地上先建两条内部道路AE,EF,如图(2)所示,点E在边界CD上,且道路EF与边界BC互相垂直,垂足为F,为节约成本,欲将道路AE,EF分别建成水泥路、砂石路,每1km的建设费用分别为
、a元(a为常数);若设
,试用
表示道路AE,EF建设的总费用
(单位:元),并求出总费用
的最小值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aa8f4d2626f09d229d8d25c2d7706d3a.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/1/299a0311-2f5e-4963-a78e-f3492663db00.png?resizew=232)
(I)如果边界AD与AB所形成的角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9eee296a7d9fba487f1485c61580196f.png)
(II)当边界AD与CD垂直,AB与BC垂直时,为后期开发方便,拟在这块空地上先建两条内部道路AE,EF,如图(2)所示,点E在边界CD上,且道路EF与边界BC互相垂直,垂足为F,为节约成本,欲将道路AE,EF分别建成水泥路、砂石路,每1km的建设费用分别为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a24d95e0548b340af8783a57bdfd05b6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60e66ed02b303ae107edefdb6ac3bad6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c24095e409b025db711f14be783a406c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5d54a032e273b515ed2d0e0aebc2217e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5d54a032e273b515ed2d0e0aebc2217e.png)
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解答题-问答题
|
适中
(0.65)
【推荐2】如图所示,有
、
、
三座城市,
城在
城的正西方向,且两座城市之间的距离为
;
城在
城的正北方向,且两座城市之间的距离为
.由
城到
城只有一条公路
,甲有急事要从
城赶到
城,现甲先从
城沿公路
步行到点
(不包括
、
两点)处,然后从点
处开始沿山路
赶往
城.若甲在公路上步行速度为每小时
,在山路上步行速度为每小时
,设
(单位:弧度),甲从
城赶往
城所花的时间为
(单位:
).
![](https://img.xkw.com/dksih/QBM/2018/6/30/1978411039211520/1979887858663424/STEM/6d8c56b1ab0f4ee8a7aa3230ae1ce503.png?resizew=160)
(1)求函数
的表达式,并求函数的定义域;
(2)当点
在公路
上何处时,甲从
城到达
城所花的时间最少,并求所花的最少的时间的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2e2aca2a5133d7134f8f29411d21bdc0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2e2aca2a5133d7134f8f29411d21bdc0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2cdba1337ec85fa9722cb4b320a82ae6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a759eecfb2f8aa1b818301675464ba13.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5e33caa1b943bd16a6ba161ed9ffa485.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/096727a1bc7ffa667e16ece427c88384.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd288d4152caf5fc8187a1a901c8949f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fe20ba65a5a470ca5886b99ff4bcc8e1.png)
![](https://img.xkw.com/dksih/QBM/2018/6/30/1978411039211520/1979887858663424/STEM/6d8c56b1ab0f4ee8a7aa3230ae1ce503.png?resizew=160)
(1)求函数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08f0ef6501db2e606ab5150ecef0f539.png)
(2)当点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
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