已知|ab-2|与|b-1|互为相反数,试求代数式1/ab+1/(a+1)(b+1)+1/(a+2)(b+2)+…+1/(a+2008)(b+2008)

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已知|ab-2|与|b-1|互为相反数,试求代数式1/ab+1/(a+1)(b+1)+1/(a+2)(b+2)+…+1/(a+2008)(b+2008)
已知|ab-2|与|b-1|互为相反数,试求代数式1/ab+1/(a+1)(b+1)+1/(a+2)(b+2)+…+1/(a+2008)(b+2008)

已知|ab-2|与|b-1|互为相反数,试求代数式1/ab+1/(a+1)(b+1)+1/(a+2)(b+2)+…+1/(a+2008)(b+2008)
|ab-2|与|b-1|互为相反数,|ab-2|与|b-1|都非负,说明:
ab-2=0
b-1=0可知:a=2.,b=1
1/ab+1/(a+1)(b+1)+1/(a+2)(b+2)+…+1/(a+2008)(b+2008)
利用1/n(n+1)=1/n-1/(n+1)【列项求和】
原式=1-1/2+1/2-1/3……-1/2009+1/2009-1/2010=2009/2010