已知|ab+2|+|a+1|=0,求下列式子的值:(a-1)(b+1)分之1+(a-2)(b+2)分之1+……+(a-100)(b+100)分之1=?

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已知|ab+2|+|a+1|=0,求下列式子的值:(a-1)(b+1)分之1+(a-2)(b+2)分之1+……+(a-100)(b+100)分之1=?

已知|ab+2|+|a+1|=0,求下列式子的值:(a-1)(b+1)分之1+(a-2)(b+2)分之1+……+(a-100)(b+100)分之1=?
已知|ab+2|+|a+1|=0,求下列式子的值:
(a-1)(b+1)分之1+(a-2)(b+2)分之1+……+(a-100)(b+100)分之1=?

已知|ab+2|+|a+1|=0,求下列式子的值:(a-1)(b+1)分之1+(a-2)(b+2)分之1+……+(a-100)(b+100)分之1=?
ab+2=0
a+1=0
∴a=-1
b=2
(a-1)(b+1)分之1+(a-2)(b+2)分之1+……+(a-100)(b+100)分之1
=-(1/2*3+1/3*4+1/4*5+……+1/101*102)
=-(1/2-1/3+1/3-1/4+1/4-1/5+1/4-……-1/101+1/101-1/102)
=-(1/2-1/102)
=-25/51