候鸟每年都要随季节的变化而进行大规模地迁徙,研究某种鸟类的专家发现,该种鸟类的飞行速度v(单位:m/s)与其耗氧量M之间的关系为:
,(其中a,b是实数),据统计,该种鸟类在静止的时间其耗氧量为45个单位,而其耗氧量为105个单位时,其飞行速度为1m/s.
(1)求出a,b的值;
(2)若这种鸟类为赶路程,飞行的速度不能低于2m/s,则其耗氧量至少要多少个单位.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df5a26dcb370df6396b294e2c250e236.png)
(1)求出a,b的值;
(2)若这种鸟类为赶路程,飞行的速度不能低于2m/s,则其耗氧量至少要多少个单位.
更新时间:2019-09-08 00:21:19
|
相似题推荐
解答题-问答题
|
适中
(0.65)
名校
解题方法
【推荐1】设函数
(
且
)是定义域为
的奇函数,
.
(1)求函数
的解析式;
(2)若
在
上的最小值为
,求
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d5bda9e69bcf53e0821f3388b56eae7c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/94440d3e4c073f94f2b266ff99d50e74.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c400a615a16a1662de98dfb4e49d58d3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a43b2faa4f81f32d94612dce724e772b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/56fbec93189276445b83c6df4e9f4866.png)
(1)求函数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09f86f37ec8e15846bd731ab4fcdbacd.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cc1b6a97182bf7e313389bd039241974.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d7dcdd87d593df4a5c5e98d47fe1cfa6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/274a9dc37509f01c2606fb3086a46f4f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
【推荐2】(1)已知
是一次函数,若
,求
.
(2)已知
为二次函数且
;求
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4fe7d5809da02c15a43a0e9a898b9086.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a86fb2da321e813aede9f7118fcde64a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4fe7d5809da02c15a43a0e9a898b9086.png)
(2)已知
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09f86f37ec8e15846bd731ab4fcdbacd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/95696c5992f892af21d53e90c726a458.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4fe7d5809da02c15a43a0e9a898b9086.png)
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
名校
解题方法
【推荐3】某公园有一块如图所示的区域OACB,该场地由线段OA,OB,AC及曲线段BC围成;经测量,
,
米,曲线段BC是以OB为对称轴的抛物线的一部分,点C到OA,OB的距离都是50米;现拟在该区域建设一个矩形游乐场OEDF,其中点D在线段AC或曲线段BC上,点E,F分别在线段OA,OB上,且该游乐场最短边长不低于25米;设
米,游乐场的面积为S平方米;
![](https://img.xkw.com/dksih/QBM/editorImg/2023/5/1/7819bba1-0508-4ffb-a8bb-f75d8e46834e.png?resizew=133)
(1)以点O为原点,试建立平面直角坐标系,求曲线段BC的方程;
(2)求面积S关于x的函数解析式
;
(3)试确定点D的位置,使得游乐场的面积S最大(结果精确到0.1米);
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/20ccc37b189fa2cbc269ca0b233dac37.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4ce1435622e153e6d5d6a417fd51b277.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d30747569ae3b6b493273f0b190e1932.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/5/1/7819bba1-0508-4ffb-a8bb-f75d8e46834e.png?resizew=133)
(1)以点O为原点,试建立平面直角坐标系,求曲线段BC的方程;
(2)求面积S关于x的函数解析式
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3105bd82be20cc7540d68aa81fb0cb27.png)
(3)试确定点D的位置,使得游乐场的面积S最大(结果精确到0.1米);
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
名校
【推荐1】如图所示,河(阴影部分)的两岸分别有生活小区
和
,其中
,
,
,
,
,
三点共线,
与
的延长线交于点
,测得
千米,
千米,
千米,
千米,若以
,
所在直线分别为
,
轴建立平面直角坐标系
,则河岸
可看成是函数
(其中
,
是常数)图象的一部分,河岸
可看成是函数
(其中
,
为常数)图象的一部分.
![](https://img.xkw.com/dksih/QBM/2020/11/27/2602105794478080/2604789873303552/STEM/d1c7b5410f134dff95bce1f2a0c76007.png?resizew=151)
(1)写出点
和点
的坐标,并求
,
,
,
的值.
(2)现准备建一座桥
,其中
在曲线段
上,
在
上,且
.记
的横坐标为
.
①写出桥
的长
关于
的函数关系式
,并标明定义域;(注:若点
的坐标为
,则桥
的长
可用公式
计算)
②当
为何值时,
取到最小值?最小值是多少?
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/134ef0b1a2669a09f05bd4dc2496f706.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/080db3af81b29ed10144a1c2e2a4fb8a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/508f8d607c633e9b008d48ac3dcd22e2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7aa30a9ee227af2b387cf6e028c20d7d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/00bab17635a999236e8d2e35017a208d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7dea2ae9d515f9ab351ad72306b776ee.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5621174446edc69848b8db5ec0958219.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/076c968214a7e6681b56e3a008cd09a5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cad74209d9457e10e01f4d81505e6312.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dc9e9e142191d1712ef4571941091fa4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef4113c492885ba7c47fe42ac792578f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/683c590673eece14fea3319c4fd5eb55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7ee31829d0d4d5f779a957d7df8058ab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4cc90520c56219486a0f3ce8fe6b6eee.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c94bb12cee76221e13f9ef955b0aab1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15b256345d7109e081b7c895591e995d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
![](https://img.xkw.com/dksih/QBM/2020/11/27/2602105794478080/2604789873303552/STEM/d1c7b5410f134dff95bce1f2a0c76007.png?resizew=151)
(1)写出点
![](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/f0a532e15e232cb4b99a8d4d07c89575.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c94bb12cee76221e13f9ef955b0aab1.png)
(2)现准备建一座桥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411461db15ee8086332c531e086c40c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/66fae8e33cd86fa8dab72704eaafe1ba.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36a1b09c653185842513e24ebba60bb3.png)
①写出桥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411461db15ee8086332c531e086c40c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36a1b09c653185842513e24ebba60bb3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/edfa37a631c89018536816cde38cf468.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c10e08a0309576bb04c2a194d7ef989a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411461db15ee8086332c531e086c40c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9f982b8388e74e1d4071a99d7e4e189a.png)
②当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36a1b09c653185842513e24ebba60bb3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
名校
解题方法
【推荐2】中国茶文化博大精深,小明在茶艺选修课中了解到,不同类型的茶叶由于在水中溶解性的差别,达到最佳口感的水温不同.为了方便控制水温,小明联想到牛顿提出的物体在常温环境下温度变化的冷却模型:如果物体的初始温度是
,环境温度是
,则经过时间
(单位:分)后物体温度
将满足:
,其中
为正的常数.小明与同学一起通过多次测量求平均值的方法得到
初始温度为98℃的水在19℃室温中温度下降到相应温度所需时间如表所示:
(1)请依照牛顿冷却模型写出冷却时间
(单位:分)关于冷却水温
(单位:℃)的函数关系,并选取一组数据求出相应的
值(精确到0.01).
(2)“碧螺春”用75℃左右的水冲泡可使茶汤清澈明亮,口感最佳.在(1)的条件下,
水煮沸后在19℃室温下为获得最佳口感大约冷却___________分钟左右冲泡,请在下列选项中选择一个最接近的时间填在横线上,并说明理由.
A.5 B.7 C.10
(参考数据:
,
,
,
,
)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/25f64fa38725c136504f723019a18dc5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1a4438bae1705c0f26beddf41322c087.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36a1b09c653185842513e24ebba60bb3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c24095e409b025db711f14be783a406c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9b4136fb930bcd68e91dc3d685d3e286.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/75355b802e13490c8592a2e59fff9188.png)
从98℃下降到90℃所用时间 | 1分58秒 |
从98℃下降到85℃所用时间 | 3分24秒 |
从98℃下降到80℃所用时间 | 4分57秒 |
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36a1b09c653185842513e24ebba60bb3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c24095e409b025db711f14be783a406c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
(2)“碧螺春”用75℃左右的水冲泡可使茶汤清澈明亮,口感最佳.在(1)的条件下,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/75355b802e13490c8592a2e59fff9188.png)
A.5 B.7 C.10
(参考数据:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e56c295ab6045e8e0cb85d80585412a0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2ab604d33f8b01e4257da2749e2d428d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c2b6864a56a55f5263204fe3dbca5216.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9112e6da071b4d6d8ce62d37340137d3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3e9d4ea3601506dbbcaecfd44e490f40.png)
您最近一年使用:0次