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数学
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(-1X1/2)+(-1/2X1/3)+(-1/3X1/4)+……(-1/2012X1/2013)=
这道题的解题方法,星期一就要期中了这货就要疯了SO……
人气:239 ℃ 时间:2020-06-22 17:09:25
解答
原式=-(1-1/2+1/2-1/3+1/3-1/4+...+1/2012-1/2013)
=-(1-1/2013)
=-2012/2013
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