一辆运输车以每小时60公里的速度从A驶往B地,2小时后到达B地,并停留了30分钟来卸货.然后卡车以每小时80公里的速度返回A地.问：试建立卡车与A地的距离y（公里）与时间t（时间）之间的函数

一辆运输车以每小时60公里的速度从A驶往B地,2小时后到达B地,并停留了30分钟来卸货.然后卡车以每小时80公里的速度返回A地.问：试建立卡车与A地的距离y（公里）与时间t（时间）之间的函数
一辆运输车以每小时60公里的速度从A驶往B地,2小时后到达B地,并停留了30分钟来卸货.然后卡车以每小时80公里的速度返回A地.
问：试建立卡车与A地的距离y（公里）与时间t（时间）之间的函数关系式,并析出定义域；
2）当卡车离开A地3小时的时候,卡车离A地的距离是多少.
第一个我知道是y=60t
第二个y=120 是什么意思啊 还有回去的函数我也不懂俄,求讲解亚~~~~~~~

一辆运输车以每小时60公里的速度从A驶往B地,2小时后到达B地,并停留了30分钟来卸货.然后卡车以每小时80公里的速度返回A地.问：试建立卡车与A地的距离y（公里）与时间t（时间）之间的函数
AB两地距离为：60*2=120公里
当0

y=60*2-（3-2-0.5）*80
60*2是A和B之间的距离，问3个小时候车距A多远 用B到A的距离减去卡车往回走 的距离
就得出Y了

1） ①y=60t ( 0≤ t ≤ 2)
②y=120 (2 ≤ t ≤ 2.5)
③y=120-80(t-2.5) (2.5 ≤ t ≤ 4)
（2）t=3代入③得y=80
y=120的意思是卡车2小时后到达B地，并停...

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1） ①y=60t ( 0≤ t ≤ 2)
②y=120 (2 ≤ t ≤ 2.5)
③y=120-80(t-2.5) (2.5 ≤ t ≤ 4)
（2）t=3代入③得y=80
y=120的意思是卡车2小时后到达B地，并停留了30分钟，停留半小时A，B的距离就是每小时60公里所走的2小时的路程
③y=120-80(t-2.5) (2.5 ≤ t ≤ 4)
从B点返回时距A的距离

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I most adore each other around the shoulder of your special ball to push Guo Bin
Wang Nan, Guo Bin
Olympic ping pong champion Wang Nan and her husband Guo Bin guest CCTV "art of life", the t...

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I most adore each other around the shoulder of your special ball to push Guo Bin
Wang Nan, Guo Bin
Olympic ping pong champion Wang Nan and her husband Guo Bin guest CCTV "art of life", the theme of the program would be to sing china group of "love." Adore each other around this subject, Wang Nan discussed his career in ping pong and adore each other the life span of sentiment.
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Instantly, Wang Nan, explains: "Since 2004, the peak of my playing career is finished, to participate in within the 2008 Beijing Olympic Games is really a dream personally,wholesale jeans, but also skilled numerous difficulties. To reach final ,wholesale nike air shox shoes, with Zhang Yining beat like one people for the final, I've completed the task, or perhaps is that if you ask me they have a perfect ending. football on television I believe the whole (process) is a place to appreciate the process, therefore the output following I finished I didn't really feel particularly painful, I think I was especially happy, but also a relief. "from athletes to his wife, your life, the role of conversion, Wang Nan wish to thank so many individuals," I wish to thank the too many people, because of the parents prior to and then flourish in their careers when, due to the coach now entered a brand new stage of life,wholesale cheap clothes, I believe it's like to thank my better half.

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