|a-1|+|ab-2|=0
所以a-1=0,ab-2=0
a=1
b=2/a=2
所以原式=1/1×2+1/2×3+……+1/2005×2006
=1-1/2+1/2-1/3+……+1/2005-1/2006
=1-1/2006
=2005/2006
|a-1|+|ab-2|=0
所以a-1=0,ab-2=0
a=1
b=2/a=2
所以原式=1/1×2+1/2×3+……+1/2005×2006
=1-1/2+1/2-1/3+……+1/2005-1/2006
=1-1/2006
=2005/2006