一乘二分之一加二乘三分之一加三乘四分之一........二零一零乘二零一一分之一 这道数学题怎么运算??

2024-11-16 15:13:21
推荐回答(3个)
回答(1):

1*1/2+2*1/3+3*1/4+......+2010*1/2011
=(1-1/2)+(1/2-1/3)+(1/3-1/4)+......+(1/2010-1/2011)
=1-1/2+1/2-1/3+1/3-1/4+......1/2010-1/2011
=1-1/2011
=2010/2011
打字累死了,多给点分吧

回答(2):

1/n(n+1)=1/n-1/(n+1)
1/1×2+1/2×3+.....+1/2010*2011
=1-1/2+1/2-1/3+1/3-1/4+...1/2009-1/2010.+1/2010-1/2011
=1-1/2011
=2010/2011

回答(3):

1/(1*2)+1/(2*3)+1/(3*4)+……+1/(2010*2011)
=(1-1/2)+ (1/2-1/3)+ (1/3-1/4)+……+(1/2010-1/2011)
=1-1/2011
=2010/2011