题目内容
观察下列等式:
+
=1;
+
+
+
=12;
+
+
+
+
+
=39;
……
则当m<n且m,n∈N时,
+
+
+
+…+
+
=________(最后结果用m,n表示).
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824035404855325.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824035404871383.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824035404902377.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824035404918411.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824035404918421.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824035404933355.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824035404949443.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824035404964416.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824035404980431.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824035404996462.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824035405011431.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824035405027433.png)
……
则当m<n且m,n∈N时,
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824035405058548.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824035405074592.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824035405089588.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824035405105583.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824035405120549.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824035405152509.png)
n2-m2
由
+
=1,知m=0,n=1,1=12-02;
由
+
+
+
=12,知m=2,n=4,12=42-22;
由
+
+
+
+
+
=39,
知m=5,n=8,39=82-52;
………
依此规律可归纳,
+
+
+
+…+
+
=n2-m2.
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824035404855325.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824035404871383.png)
由
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824035404902377.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824035404918411.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824035404918421.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824035404933355.png)
由
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824035404949443.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824035404964416.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824035404980431.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824035404996462.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824035405011431.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824035405027433.png)
知m=5,n=8,39=82-52;
………
依此规律可归纳,
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824035405058548.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824035405074592.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824035405089588.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824035405105583.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824035405120549.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824035405152509.png)
![](http://thumb.zyjl.cn/images/loading.gif)
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