︱a-1︱+︱ab-2 ︱=0 a+b/1+(a+1)(b+1)/1+(a+2)(b+2)/1+(a+3)(b+3)/1……+(a+2005)(b+2006)/1

问题描述:

︱a-1︱+︱ab-2 ︱=0 a+b/1+(a+1)(b+1)/1+(a+2)(b+2)/1+(a+3)(b+3)/1……+(a+2005)(b+2006)/1
写错了题目是 ︱a-1︱+︱ab-2 ︱=0 1/ab+1/(a+1)(b+1)+1/(a+2)(b+2)+1/(a+3)(b+3)……+1/(a+2005)(b+2006) 写出思路。

︱a-1︱+︱ab-2 ︱=0
a-1=0 a=1 ab-2=0 b=2
a+b/1+(a+1)(b+1)/1+(a+2)(b+2)/1+(a+3)(b+3)/1……+(a+2005)(b+2005)/1
=1-1/2+1/2-1/3+……+1/2006-1/2007
=2006/2007