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如果有理数a,b满足|ab-2|+(1-b)²=0,试求1/ab+1/(a+1)(b+1)+1/(a+2)(b

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如果有理数a,b满足|ab-2|+(1-b)²=0,试求1/ab+1/(a+1)(b+1)+1/(a+2)(b+2)+…+1/(a+2007)(b+2007)的值
如果有理数a,b满足|ab-2|+(1-b)²=0,试求1/ab+1/(a+1)(b+1)+1/(a+2)(b
因为(a-1)²+|ab-2|=0
所以:a-1=0,a=1
ab-2=0,b=2
1/ab+1/[a+1][b+1]+1/[a+2][b+2]+……+1/[a+2007][b+2007]
=1/(1*2)+1/(2*3)+1/(3*4)+...+1/(2008*2009)
=1/1-1/2+1/2-1/3+1/3-1/4+...+1/2008-1/2009
=1-1/2009
=2008/2009