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楼1970-01-01 08:00:00
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黄文念

铁杆木虫 (小有名气)


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小木虫(金币+0.5):给个红包,谢谢回帖交流
好好学一下英文中的身份和基础就不会问这样的问题了!
8楼2011-01-02 01:04:06
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我们的书上叫它 I。
2楼2010-12-31 16:21:50
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inhaul

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wangyujia(金币+10):呵呵!谢谢啊!我怎么忘了在维基上搜一下呢?谢谢! 2011-01-01 19:43:15
Some mathematics books use U and E to represent the Identity Matrix (meaning " Unit Matrix" and "Elementary Matrix", or from the German "Einheitsmatrix", respectively), although I is considered more universal.
http://en.wikipedia.org/wiki/Identity_matrix
3楼2010-12-31 17:05:00
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ssszhangxx

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单位矩阵为什么又叫E?
这个问题很奇怪,E只是表示单位矩阵的一个符号,单位矩阵就是单位矩阵,它没有一个名字叫E。
5楼2010-12-31 20:36:04
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2010-12-31 20:09   回复  
引用回帖:
Originally posted by inhaul at 2010-12-31 19:05:00: Some mathematics books use U and E to represent the Identity Matrix (meaning " Unit Matrix" and "Elementary Matrix", or from the German "Einheitsmatrix", respectively) ...

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