已知|ab=2|+(a+1)^2=0,求下列式子的值:1/(a-1)(b+1)+1\(a-2)(b+2)+……+1/(a-100)(b+100).

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已知|ab=2|+(a+1)^2=0,求下列式子的值:1/(a-1)(b+1)+1\(a-2)(b+2)+……+1/(a-100)(b+100).

已知|ab=2|+(a+1)^2=0,求下列式子的值:1/(a-1)(b+1)+1\(a-2)(b+2)+……+1/(a-100)(b+100).
已知|ab=2|+(a+1)^2=0,求下列式子的值:1/(a-1)(b+1)+1\(a-2)(b+2)+……+1/(a-100)(b+100).

已知|ab=2|+(a+1)^2=0,求下列式子的值:1/(a-1)(b+1)+1\(a-2)(b+2)+……+1/(a-100)(b+100).
已知|ab+2|+(a+1)^2=0
因为|ab+2|≥0,(a+1)^2≥0
所以,当它们之和为零时,必然是两者同时为零
所以,ab+2=0,a+1=0
所以,a=-1,b=2
所以原式=1/[(-2)*3]+1/[(-3)*4]+……+1/[(-101)*102]
=-[1/(2*3)+1/(3*4)+……+1/(101*102)]
=-[(1/2)-(1/3)+(1/3)-(1/4)+……+(1/101)-(1/102)]
=-[(1/2)-(1/102)]
=-25/51

已知不成立

|ab+2|+|a+1|=0
得a+1=0,ab+2=0
解得a=-1,b=2
1/(a-1)(b+1)+1/(a-2)(b+2)+···+1/(a-2005)(b+2005)
=1/(-2)(3)+1/(-3)(4)+....+1/(-2006)(2007)
=-(1/2*3+1/3*4..............+1/2006*2007)
=-(1/2-1/3+1/3-1/4+........+1/2006-1/2007)
=-(1/2-1/2007)
=-2005/4014