It's constant pressure. OK, so now, last time you looked at the Joule expansion to teach you how to relate derivatives like du/dV.

这是恒压的，好，上节课你们,学习了焦耳定律,以及怎样进行导数间的变换。

麻省理工公开课 - 热力学与动力学课程节选

At my maximum, I'll put a hat over it to indicate this is the argmax; at my maximum I'm going to set this thing equal to 0.

给每个最大值都标注上一个帽来,在最大值处导数方程等于0

耶鲁公开课 - 博弈论课程节选