1乘3分之一加3乘5分之1加5乘7分之1.具体的看补充.简便算法1 1 1 1------ + ------ + ------ + .+ ----------------=__________1×3 3×5 5×7 2011×2013麻烦讲清楚一点!

1乘3分之一加3乘5分之1加5乘7分之1.具体的看补充.简便算法1 1 1 1------ + ------ + ------ + .+ ----------------=__________1×3 3×5 5×7 2011×2013麻烦讲清楚一点!
1乘3分之一加3乘5分之1加5乘7分之1.具体的看补充.简便算法
1 1 1 1
------ + ------ + ------ + .+ ----------------=__________
1×3 3×5 5×7 2011×2013
麻烦讲清楚一点!

1乘3分之一加3乘5分之1加5乘7分之1.具体的看补充.简便算法1 1 1 1------ + ------ + ------ + .+ ----------------=__________1×3 3×5 5×7 2011×2013麻烦讲清楚一点!
拆数法知道吗.答案是（1-2013分之一）乘2分之1.（1-1/3+1/3-1/5...+1/2012-1/2013）×1/2就是（1-1/2013）×1/2=1006/2013
就请给个采纳吧.
不明白加Q974852550

把每个分式都拆开来变成1 1 1 1 1 1 1 1 1 1
---×---+---×---+---×.---+....+------×------- + ------×------ 是不是看出规律来
...

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把每个分式都拆开来变成1 1 1 1 1 1 1 1 1 1
---×---+---×---+---×.---+....+------×------- + ------×------ 是不是看出规律来
1 3 3 5 5 7 2009 2011 2011 2013
了，然后提取公因式

收起

原式可以变为：1/2（1-1/3+1/3-1/5+1/5-1/7+1/7+...+1/2011-1/2013）
=1/2（1-1/2013）
=1/2*2012/2013
=1006/2013
如果对了，支持我一下。谢谢。

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