x=2,y=1.求xy/1+(x+1)(y+1)/1+...+(x+2010)(y+2010)/1的值.

来源：学生作业帮编辑：作业帮分类：数学作业时间：2024/07/04 18:00:09

你题目是不是写倒了?
是1/xy + 1/(x+1)(y+1)+...+ 1/(x+2010)(y+2010) 吧?就是它们的倒数相加
x=2,y=1
1/xy + 1/(x+1)(y+1)+...+ 1/(x+2010)(y+2010)
=1/(2×1) + 1/(3×2) + 1/(4×3) + ... + 1/(2012×2011)
= [(1/1)-(1/2)] + [(1/2)-(1/3)] + [(1/3)-(1/4)] +...+ [(1/2011)-(1/2012)]
=1- 1/2012 (中间全都约掉了)
=2011/2012

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