2020年新冠病毒爆发,许多志愿者积极参加抗疫活动.现有甲、乙两位志愿者同时徒步从A地出发赶往C地,甲不经B地直接匀速前往C地,他的速度(单位:千米/小时)范围由函数
决定:乙经B地接人后前往C地,速度为8千米/小时,此间在B地停留15分钟,其中AC=5千米,AB=4千米,BC=2千米,如图.
![](https://img.xkw.com/dksih/QBM/2020/7/27/2515068841705472/2515147582939136/STEM/7812f4d9763c4e9e807f51b8a1a747c4.png?resizew=228)
(1)求v(x)的取值范围;
(2)若甲以最快速度赶往C地,且志愿者的对讲机的有效通话距离是3千米,试问这一路上甲、乙两人的对讲机是否能正常通话?请说明理由.
(3)甲、乙到达C地后原地等待,为使两位志愿者在C处互相等待的时间不超过1小时,甲的速度v(x)中x应控制在什么范围内?
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a7fcd9353491f1a674533dac241ddea.png)
![](https://img.xkw.com/dksih/QBM/2020/7/27/2515068841705472/2515147582939136/STEM/7812f4d9763c4e9e807f51b8a1a747c4.png?resizew=228)
(1)求v(x)的取值范围;
(2)若甲以最快速度赶往C地,且志愿者的对讲机的有效通话距离是3千米,试问这一路上甲、乙两人的对讲机是否能正常通话?请说明理由.
(3)甲、乙到达C地后原地等待,为使两位志愿者在C处互相等待的时间不超过1小时,甲的速度v(x)中x应控制在什么范围内?
更新时间:2020-07-27 22:23:46
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