And the context of sorting, the worst case is your handed a problem that's in complete reverse order because that implies you have - to do as more work that could possibly-- that you could-- you have to do more work than you would of course if things were in perfect order.

在排序的环境中，最糟糕的情况是待排序的序列是,完全逆序的，在这种情况下,你不得不做更多的工作-,比起一个较理想顺序的序列,你必须花费更多的努力。

哈佛公开课 - 计算机科学课程节选

Mathematically complete problem is that you can find the function x of t by saying that the second derivative of the function is equal to -k over m times the function.

这个数学问题就是,你可以求出函数 x,只要令函数的二阶导数,等于 -k 除以 m 再乘以函数

耶鲁公开课 - 基础物理课程节选