若|a-1|+|b-2|=o 求1/ab+1/(a+1)(b+1)+...1/(a+2006)(b+2006)的值
问题描述:
若|a-1|+|b-2|=o 求1/ab+1/(a+1)(b+1)+...1/(a+2006)(b+2006)的值
答
|a-1|+|b-2|=0则a=1 b=21 / ab+1/ (a+1)(b+1)+1/(a+2)(b+2)+……+1/(a+2006)(b+2006)=1/1×2 +1/2×3 +1/3×4 +……+1/2007×2008=1-1/2 + 1/2-1/3 +1/3-1/4 +……+ 1/2007-1/2008=1-1/2008=2007/2...