100分求一道数学题,A population has been growing exponentially.In 1960,it was 50,000 and in 1965,it was100,000.What was the population in 1970?我知道答案是200000,

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100分求一道数学题,A population has been growing exponentially.In 1960,it was 50,000 and in 1965,it was100,000.What was the population in 1970?我知道答案是200000,
100分求一道数学题,
A population has been growing exponentially.In 1960,it was 50,000 and in 1965,it was
100,000.What was the population in 1970?
我知道答案是200000,

100分求一道数学题,A population has been growing exponentially.In 1960,it was 50,000 and in 1965,it was100,000.What was the population in 1970?我知道答案是200000,
人口数呈指数增长(growing exponentially),也就是说,某年的人口数是前一年的n倍,则可知第五年为起始年份的n^5倍,设1960年为A1,1965年为A2,则1970年为A3,则A3=n^5*A2,A2=n^5*A1
A1=50000,A2=100000,则n^5=2,则A3=2*A2=200000

人口数呈指数增长(growing exponentially),假设1960年为A₁=50000,1965年为A₂=100000=A₁×2¹,则
A₃=A₁×2²=50000×4=200000

人口增长的很快。在1960年,有50000人,在1965年有100000人。那么在1970年人口是多少?
从1960到1965年,五年时间内人口增长了一倍,由50千到了100千,那么再过五年就会由100千增长一倍到200千。所以答案是200000

意思事人口呈指数形式增长
设人口函数为:y=A*Exp(B*x) y为人口,x为年代-1960
则A=50000
y(1965)=100000=50000*Exp(5*B)
Exp(5*B)=2
y(1970)=50000*Exp(10*B)=50000*[Exp(5*B)]*[Exp(5*B)]
=200000