You can actually take derivatives of a vector with time.

你可以直接求位矢对时间的导数

耶鲁公开课 - 基础物理课程节选

This vector i prime has got a horizontal part, This kind of trigonometry you should know all the time.

矢量 i' 有一个水平方向的分量,这类三角关系你们应该已经很熟悉了

耶鲁公开课 - 基础物理课程节选

to the n, every value in the 1 bit vector we looked at last time is either 0 or 1. So it's a binary n number of n bits, 2 to the n.

从2到n，我们上次看到的,位向量的每个值不是0就是,所以它是n，比特的二进制数,从2到。

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