1+1/2+1/3+2/3+1/4+2/4+3/4+...59/60

来源：学生作业帮助网编辑：作业帮时间：2024/11/08 20:45:50

1+1/2+1/3+2/3+1/4+2/4+3/4+...59/60
1+1/2+1/3+2/3+1/4+2/4+3/4+...59/60

1+1/2+1/3+2/3+1/4+2/4+3/4+...59/60
1/n+2/n+……+(n-1)/n
=([1+2+……+(n-1)]/n
=[n(n-1)/2]/n
=(n-1)/2
所以原式=1+1/2+2/2+3/2+……+59/2
=1+(1+2+……+59)/2
=1771

(1-1/2^2)(1-1/3^2)(1-1/4^2).(1-1/2009^2), 1+2+3+4+1 1/(2^3)+1/(2^3+1)+1/(2^3+2)+1/(2^3+3)+...+1/(2^4-1) 1 2 3 4 1 2 3 4 1 2 3 4 1,2,3,4, 1 2 3 4 1 2 3 4 1,2,3,4, 1,2,3,4, 1,2,3,4, 1,2,3,4, 1 2 3 4 1,2,3,4, 1,2,3,4, 1,2,3,4, 1、2、3、4