If you had one negative number in it, then the product would be a negative number and, if you took a root of that, then you might get an imaginary number.

如果这当中有一个负数,乘积就会变成负的,如果你对一个负数开根号,你就会得到一个虚数

耶鲁公开课 - 金融市场课程节选

While behaviors have evolved, the change in relationships can help people encourage the positive behaviors the church needs and root out the negative behaviors that are getting in the way.

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Richey: That's the other half of what we see as a root cause of the past decade of flat or negative returns for the typical U.S.-based equity investor: they've been seriously under-exposed to International stocks over the past decade.

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