它只有关于每个变量的偏导数。

It has only partial derivatives for each variable.

youdao

好的，那就是偏导数的定义。

OK, so that's the definition of a partial derivative.

youdao

我们还要试图理解偏导数。

We are trying to understand partial derivatives.

youdao

因此，我们应该重新理解偏导数的含义。

So, we have to figure out what we mean by partial derivatives again.

youdao

当遇到偏导数时，一定记住，不能约分。

Somehow, when you have a partial derivative, you must resist the urge of simplifying things.

youdao

我们已经发现,它由f对x的偏导数给出。

Well, we have seen that it is given by the partial derivative f sub x.

youdao

我是说现在已经有两个一阶偏导数。

I mean we already have two first derivatives.

youdao

对n的偏导数，这里的n是摩尔数。

With respect to n, the number of moles.

youdao

同样地，梯度也是把偏导数糅合到一起。

Well, the gradient is also a way to package partials together.

youdao

设，在上有连续的偏导数。

Suppose and have continuous partial derivatives on.

youdao

我们说一个函数是可微的，如果这些偏导数存在。

And, we say that a function is differentiable if these things exist.

youdao

偏微分方程就是，跟函数各个偏导数有关的方程。

A partial differential equation is an equation that involves the partial derivatives of a function.

youdao

偏微分方程就是，跟函数各个偏导数有关的方程。

A partial differential equation is an equation that involves the partial derivatives of a function.

youdao