This is a discontinuous payoff function, so differentiating isn't going to get you very far.

这是一个不连续的收益函数,所以不会涉及太多微分的东西

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He reasoned then that the charge, since he could vary voltage continuously but got a discontinuous variation in velocity, his conclusion was that the charge must be discontinuously attached to the droplet.

他推断出电荷，因为他可以不断地改变电压,但是得出了速度是在不连续变化着，他的结论是电荷,是间断地依附于液滴上的。

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