And all this is, is saying that when you take a mixed second derivative, it doesn't matter in which order you take the two derivatives.

麦克斯韦关系的本质是,当你考虑混合的二阶导数时，求导的顺序不影响最后的结果,现在，我们利用这些关系。

麻省理工公开课 - 热力学与动力学课程节选

I mean sometimes if you have things that are a mixture of foods, like you go out for Chinese food or you have a casserole somewhere, or you have some dish of vegetables mixed together, how do you make sense of that when it comes to entering these things into a record.

我是说,有时候有一堆食物在你面前,如出去吃中餐,或你面前有一份大杂烩,又或者是很多蔬菜混合在一块,在输入饮食记录的时候,怎样才能让你输入的东西有意义呢

耶鲁公开课 - 关于食物的心理学、生物学和政治学课程节选

And what you see when we see it with our eye, which is all the wavelengths, of course, mixed together, is whichever those wavelengths is most intense. So, when we looked at the individual neon lines, it was the orange colors that was most intense, which is why we were seeing kind of a general orange glow with the neon, which is different from what we see with the hydrogen.

当你们用眼睛看时，当然看到的是全波长，是混在一起来，看到的是最强的那些波长，当我们看单个氖谱线时，橙色是最强的,所以我们看氖光整体是橙色的,这和氢气是不一样的。

麻省理工公开课 - 化学原理课程节选