So, critical points, remember, are the points where all the partial derivatives are zero.

临界点是，偏导数都为零的点。

youdao

What we would start doing immediately is taking the partial derivatives. What is f sub x?

我们首先要做的事是,求偏导数，fx是多少？

youdao

So the unknown is a function, and the equation will relate the partial derivatives of that function to each other.

未知量是一个函数，这个方程，将把函数的偏导数联系起来。

youdao

When you say that, it implies that the differential is given by this pair of partial derivatives.

这就意味着，内能的微分,等于偏u偏T，保持体积不变。

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