This is going to be probably a homework at some point to do this. For now, let's take it for granted. Let's take it for granted that we know how to calculate this derivative from an equation of state like this.

这可能是将来的一个课后作业,现在，请把这当成理所当然的，理所当然地认为我们,知道怎样从一个状态,方程计算这样的微分式。

麻省理工公开课 - 热力学与动力学课程节选