The orientation that will work for this theorem is choosing the normal vector to point outwards.

对于这个定理，我选择的方向是,指向外的正方向。

youdao

If I fix a point, then the gradient vector at that point is given to me.

确定一点，那么对我来说，这点的梯度向量就是确定的。

youdao

Add the access point to your location vector.

将访问点添加到位置向量中。

youdao

it's clear that you want to add a vector that looks like that, because then you go from the start of this to the finish of that, you end up at the same point and you get this invisible 0 vector.

显然应该给它加上这样一个矢量,因为从这个矢量的起点指向那个矢量的终点,最终指向的是同一个点,你就得到这个不可见的零矢量

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