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1/8, 1/4, 1/2, 3/4,7/8英寸分别是多少厘米? - 知乎
把1英寸分成8等分: 1/8 1/4 3/8 1/2 5/8 3/4 7/8 英寸。 This is an arithmetic sequence since there is a common difference between each term. In this case, adding 18 to the previous term in the …
Formal proof for $ (-1) \times (-1) = 1$ - Mathematics Stack …
Jun 13, 2020 · Is there a formal proof for $(-1) \\times (-1) = 1$? It's a fundamental formula not only in arithmetic but also in the whole of math. Is there a proof for it or is it just assumed?
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 …
Word,插入多级列表,但是改了1.1,第二章的2.1也变成1.1,随着 …
注1:【】代表软件中的功能文字 注2:同一台电脑,只需要设置一次,以后都可以直接使用 注3:如果觉得原先设置的格式不是自己想要的,可以继续点击【多级列表】——【定义新多级 …
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
factorial - Why does 0! = 1? - Mathematics Stack Exchange
Intending on marking as accepted, because I'm no mathematician and this response makes sense to a commoner. However, I'm still curious why there is 1 way to permute 0 things, …
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 …
Why is $1/i$ equal to $-i$? - Mathematics Stack Exchange
May 11, 2015 · 11 There are multiple ways of writing out a given complex number, or a number in general. Usually we reduce things to the "simplest" terms for display -- saying $0$ is a lot …
Formula for $1^2+2^2+3^2+...+n^2$ - Mathematics Stack …
$ (n+1)^3 - n^3 = 3n^2+3n+1$ - so it is clear that the $n^2$ terms can be added (with some lower-order terms attached) by adding the differences of cubes, giving a leading term in $n^3$. The …