∵|a-2|+(b-1)²=0
∵|a-2|≥0
(b-1)²≥0
∴a-2=0 a=2
b-1=0 b=1
∵a-b=2-1=1
1/(1/2) = 1- 1/2
1/(2×3) = 1/2 - 1/3
1/(3*4)=1/3 -1/4
……
1/(2009×2010) = 1/2009 - 1/2010
若1/n﹙n+1﹚=1/n-﹙1/n+1﹚ [n≠0]
∴﹙1/ab﹚+1/(a+1)(b+1) + 1/(a+2)+...+1/(a+2008﹚(b+2008)
=½+1/﹙3×2﹚+1/﹙4×3﹚+………+1/﹙2009×2008﹚
=1-½+½-1/3+1/3-1/4+1/4………-1/2008+-1/2009+1/2009-1/2010
=1-1/2010
=2009/2010