听上去你的数学比小学算数多点么,看看GYRO关于这个理论的微积分证明方法对吗?


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送交者: JFF 于 2008-10-31, 20:44:55:

回答: 小学算数, 如何算原创了个人口理论? 由 JJZ 于 2008-10-31, 17:49:25:

单愿你能看懂。


Rigorous proof by: gyro

Let \int denote integral, x denote time(year), N(x) denote the number of people at age x. Each year there are -dN/dx=-N' people die at age x. The total number of people die in a year is -\int N'dx

The average life span=\int N'xdx/\int N' dx

The average death rate is -\int N'dx/\int N dx

Integration by part,

\int N'xdx=-\int N dx

So life span x death rate = 1

This conclusion holds regardless of the variation of the death rate with age.





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