来自《耶鲁大学开放课程：基础物理 第1集 第1集》

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  The third derivative, unfortunately, was never given a name,
  遗憾的是三阶导数没有专门的名称
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  and I don't know why.
  我也不知道这是为什么
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  I think the main reason is that there are no equations
  我想主要原因是因为还没有等式
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  that involve the third derivative explicitly.
  明显涉及三阶导数
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  F=ma. The a is this fellow here,
  F=ma a就是这里的这个
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  and nothing else is given an independent name.
  其它的都没有独立命名
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  Of course, you can take a function
  当然 你可以随意拿一个函数
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  and take derivatives any number of times.
  对它求任意阶的导数
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  So you are supposed to know,
  接下来你就会知道
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  for example, if x(t) is t^(n),
  例如 如果x(t)=t^(n)
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  you're supposed to know dx/dt is nt^(n-1).
  那么dx/dt=nt^(n-1)
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  Then you're supposed to know derivatives of simple functions
  你应该知道一些简单函数的导数