So the work that Walter Lewin has to do to bring it from A to B is the integral in going from A to B of my force, dx.

所要做的功,就等于A到B的,我的力的积分,这是个点积。

youdao

Or, if you prefer, that's negative integral from a to b of M of dx.

或者你喜欢的话，那就是积分的负值,在a到b上对MdX的积分。

youdao

Then, to find the meaning of b, we take one derivative of this, dx/dt, that's velocity as a function of time, and if you took the derivative of this guy, you will find as at+b. That's the velocity of the object.

接下来,为了弄清b的含义,我们取它的一阶导数,dx/dt,得到速度作为时间的函数,如果你对它求导的话,你会得到at+b,这就是物体的速度

耶鲁公开课 - 基础物理课程节选