资本市场运作案例 豆瓣:1/ab+1/(a+1)(b+1)+1/(a+2)(b+2)……1/(a+2005)(b+2005)=?
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a=2,b=1
=1/(2*1)+1/(3*2)+1/(4*3)……1/(2007*2006)
=1-1/2+1/2-1/3+1/3-1/4……1/2006-1/2007
=1-1/2007
=2006/2007
=1/(2*1)+1/(3*2)+1/(4*3)……1/(2007*2006)
=1-1/2+1/2-1/3+1/3-1/4……1/2006-1/2007
=1-1/2007
=2006/2007