It's mortality that gives it that sense of ephemeral value, but it's also mortality that threatens to cancel it out altogether.

因为逃不过必死的结局所以给了美朝生暮死的价值，但必死性也可能带来全盘出局的威胁。

耶鲁公开课 - 1945年后的美国小说课程节选

If the time you are interested in is not zero, you're allowed to cancel it and get the time from here.

如果你们关注的解不是零时刻,那么就可以忽略它,然后从这里解出时间

耶鲁公开课 - 基础物理课程节选

Occasionally, you'll find you need to cancel out units, because, of course, you're always doing unit analysis as you solve your problems, and sometimes you'll need to convert joules to kilogram meters square per second squared.

偶然地，你会发现需要消除单位，因为在解题时,经常要做单位分析，所以有时候需要把,焦耳换做,一千克乘以米的平方除以秒的平方。

麻省理工公开课 - 化学原理课程节选

We'll substitute that in, and the T dS terms are going to cancel.

将其代入，消去TdS项。

麻省理工公开课 - 热力学与动力学课程节选

You all know that when you do dy/dx, you're not supposed to cancel that d.

你们都知道 当你算dy/dx时,你不能把d约掉

耶鲁公开课 - 基础物理课程节选

This time, the T dS terms are going to cancel.

这次TdS会被消去。

麻省理工公开课 - 热力学与动力学课程节选

You don't want to cancel the d in the derivative.

你不能在求导的时候约掉d

耶鲁公开课 - 基础物理课程节选

So, the point is whenever you have derivatives with something over dt, do not hesitate to cancel the dts This will be actually true as long as both quantities are vanishingly small.

关键在于,只要你推出的式子分母上有dt,不要犹豫,直接约掉,这个式子只在,两遍都是无穷小的情况下成立

耶鲁公开课 - 基础物理课程节选

pxa So what happens when we add a 2 p a and we subtract from it a 2 p x b, or the same with a 2 p y a subtracting a 2 p y b, is that we're actually going to cancel out the wave function in the center, so we now have 2 nodal planes.

当我们用,减去2pxb时，或者是2pya减去2pyb时，我们会消去,中间的波函数，所以现在我们有两个节面。

麻省理工公开课 - 化学原理课程节选

In addition to that, we have that epsilon nought value, remember that's the permittivity constant in a vacuum, and basically that is what we use as a conversion factor to get from units. We don't want namely coulombs to units, we want that will allow us to cancel out in this equation.

这是电子的电荷，此外，我们有epsilon零，记住这是真空的介电常数，这是我们用来转换单位的转换常数,我们不想用库伦单位，我们希望这个可以在方程中约去它。

麻省理工公开课 - 化学原理课程节选

But in terms of SI units, which become much more useful if you're actually trying to use intensity in a problem and cancel out your units, we're just talking about joules per second is what intensity is.

但是用国际单位制，这个变得越来越有用了,如果你实际上在使用强度,来解决问题和约化单位，我们仅仅讨论每秒钟的焦耳,这就是强度。

麻省理工公开课 - 化学原理课程节选

I'm going to do something which somehow we are told never, ever to do, which is to just cancel the dts.

我接下来要做一件以前绝对不允许的事情,约去这些dt

耶鲁公开课 - 基础物理课程节选

T1 I can cancel those, T2 and then I'm going to multiply through by T1.

然后乘以，所以这等于T2除以T1减。

麻省理工公开课 - 热力学与动力学课程节选