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知乎，中文互联网高质量的问答社区和创作者聚集的原创内容平台，于 2011 年 1 月正式上线，以「让人们更好的分享知识、经验和见解，找到自己的解答」为品牌使命。
为什么 1 不能被认为是质数？ - 知乎
质数就是“只能被1和它本身整除”的自然数。 然而，我们必须在此基础之上增加一条警告，宣称数字1不是质数，这简直就像马后炮一样。
what is 1 - 1/2 + 1/3 - 1/4 + 1/5 - 1/6 + 1/7 - 1/8 +1/9
Nov 28, 2019 · Please provide additional context, which ideally explains why the question is relevant to you and our community. Some forms of context include: background and motivation, relevant …
1-1+1-1+1-1+1... 这个无穷数列的值是什么？如何证明？ - 知乎
知乎，中文互联网高质量的问答社区和创作者聚集的原创内容平台，于 2011 年 1 月正式上线，以「让人们更好的分享知识、经验和见解，找到自己的解答」为品牌使命。
abstract algebra - Prove that 1+1=2 - Mathematics Stack Exchange
Jan 15, 2013 · Possible Duplicate: How do I convince someone that $1+1=2$ may not necessarily be true? I once read that some mathematicians provided a very length proof of $1+1=2$. Can you think …
What is the value of $1^i$? - Mathematics Stack Exchange
Aug 30, 2010 · There are infinitely many possible values for $1^i$, corresponding to different branches of the complex logarithm. The confusing point here is that the formula $1^x = 1$ is not part of the …
summation - Sum of 1 + 1/2 - Mathematics Stack Exchange
How do I calculate this sum in terms of 'n'? I know this is a harmonic progression, but I can't find how to calculate the summation of it. Also, is it an expansion of any mathematical function? 1 ...
请问这个符号 '' 是什么长度单位？ - 知乎
电视外包装 英寸的符号是 " 或者inch (简写为in)。1"=1英寸 (inch)=2.54厘米，而1'=1英尺 (foot，符号ft)=12英寸 (12")=30.48厘米。 关于电视屏幕尺寸的计算 一般电视或显示器厂商宣传自家屏幕大小时 …
How can 1+1=3 be possible? - Mathematics Stack Exchange
Feb 3, 2021 · Hi, welcome to Math SE! Can you show us the proof you're looking at? There are a lot of false proofs of this sort out there, typically involving division by 0, I would imagine that's probably the …
False Proof of 1=-1 - Mathematics Stack Exchange
Aug 24, 2016 · False Proof of 1=-1 [duplicate] Ask Question Asked 9 years, 3 months ago Modified 9 years, 3 months ago