11/2+21/3+31/4+......+20071/2008

来源：百度知道编辑：UC知道时间：2024/04/28 05:03:25

1*1/2+2*1/3+3*1/4+......+2007*1/2008
＝2007－（1/2+1/3+......+1/2008)

#include<stdio.h>
void main()
{int j;
double s=0;
for(j=2;j<2009;j++)
s+=1/j;
printf("%f",s);
}
1/2+1/3+......+1/2008=7.182359
1*1/2+2*1/3+3*1/4+......+2007*1/2008=2007-7.182359=1999.8176

1+1/(1+2)+1/(1+2+3)+...+1/(1+2+3+...+100) 1+1/(1+2)+1/(1+2+3)+-------+1/(1+2+3+----+100) 1+1/1+2+1/1+2+3+...+1/1+2+3...+2000 1+1/1+2+1/1+2+3.........+1/1+2+3.....100 1*(1/1+2)*(1/1+2+3)*~~~*(1/1+2+~~~2005)=? (1+1/2)(1+1/2^2)(1+1/2^4)(1+1/2^8) (1-1/2^2)*(1-1/3^2)*(1-1/4^2).......(1-1/100^2) 1/2-1/2=? 3/2=2+1/1*2=1/1+1/2 (1/2005-1)(1/2004-1)........(1/3-1)(1/2-1)