Question

当｜ab-2｜+｜b-1｜=0 求ab分之1加上（a+1))(b+1)分之1+（a+2)(b+2）分之1+…+（a+20

Answer 1

ab-2=0,b-1=0

b=1,a=2

1/ab+1/(a+1)(b+1)+……+1/(a+2006)(b+2006)

=1/1*2+1/2*3+……+1/2007*2008

=(1-1/2)+(1/2-1/3)+……+(1/2007-1/2008)

=1-1/2008

=2007/2008