已知|ab-2|与|b-1|互为相反数.求1/ab+1/（a+2)*（b+1）+1/（a+2)*(b+2)+...+1/（a+2010)*(b+2010)

已知|ab-2|与|b-1|互为相反数.求1/ab+1/（a+2)*（b+1）+1/（a+2)*(b+2)+...+1/（a+2010)*(b+2010)
已知|ab-2|与|b-1|互为相反数.求1/ab+1/（a+2)*（b+1）+1/（a+2)*(b+2)+...+1/（a+2010)*(b+2010)

已知|ab-2|与|b-1|互为相反数.求1/ab+1/（a+2)*（b+1）+1/（a+2)*(b+2)+...+1/（a+2010)*(b+2010)
已知|ab-2|与|b-1|互为相反数.
b-1=0 b=1
ab-2=0 a=2
1/ab+1/（a+2)*（b+1）+1/（a+2)*(b+2)+...+1/（a+2010)*(b+2010)
=1/1x2+1/2x3+1/3x4+……+1/2011x2012
=1-1/2+1/2-1/3+1/3-1/4+……+1/2011-1/2012
=1-1/2012
=2011/2012

因为|ab-2|与|b-1|互为相反数
＝>ab-2=0=b-1
=>b=1 a=2
1/ab+1/（a+2)*（b+1）+1/（a+2)*(b+2)+...+1/（a+2010)*(b+2010)
=1/2+1/3*2+1/4*3+1/5*4+……+1/2012*2011
=1/2+(1/2-1/3)+(1/3-1/4)+(1/4-1/5)+……+(1/...

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因为|ab-2|与|b-1|互为相反数
＝>ab-2=0=b-1
=>b=1 a=2
1/ab+1/（a+2)*（b+1）+1/（a+2)*(b+2)+...+1/（a+2010)*(b+2010)
=1/2+1/3*2+1/4*3+1/5*4+……+1/2012*2011
=1/2+(1/2-1/3)+(1/3-1/4)+(1/4-1/5)+……+(1/2011-1/2012)
=1/2+1/2-1/2012
=1-1/2012
=2011/2012

收起

绝对值都为0，ab=2,b=1,a=2 自己带入算了