So x is not really the coordinate of the end point.

其实并不是弹簧端点的坐标

耶鲁公开课 - 基础物理课程节选

And then from that start point, get the x-value. Same thing, from that instance, get the endpoint, from that end point get the x-value, square.

取得结束点，然后取得结束点的y坐标，然后求差开平方，然后同样求的y坐标。

麻省理工公开课 - 计算机科学及编程导论课程节选

For example, if you started here and you did all this and you came back here, the average velocity would be zero, because you start and end at the same value of x, you get something; 0 divided by time will still be 0.

例如,如果你从这里开始运动,经过这个过程又回到这里,平均速度就是0,因为初态和末态的位移相同,你得到了什么呢,0除以时间还是0

耶鲁公开课 - 基础物理课程节选

What's the value of this X at the end of the day?

最终X的值是多少呢？

哈佛公开课 - 计算机科学课程节选