And now I want to add on, so I'm gonna hook the next vector on to the front of the arrow, we'll start next vector, and I will go this way, so let's see, can I do it right?

现在我要加上…我要将下一个向量钩住这个箭头的前端，我们将会开始下一个向量，我将这样做，让我们来看，我做的对么？

youdao

So I start with this vector, that’s already here.

我从这个向量开始，它已经在这边了。

youdao

Well, the first thing it means before we multiply two vectors, let's start multiplying a vector with itself That's probably easier.

我们来看它的第一个意义，在我们用两个，不一样的向量相乘之前，我们先看一个向量和它本身的点积。

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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