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Mathematics Stack Exchange
Q&A for people studying math at any level and professionals in related fields
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 …
想请大神给小白科普一下音频声道的专业知识，什么是2.1声道、5.…
Oct 27, 2024 · 5.1声道的第一次使用，追溯到1976年，当时杜比实验室修改了Todd-AO 70毫米胶片上6个类比音轨的使用方式，但当时在电影《洛根的逃亡》中杜比实验室的光学矩阵编码系 …
Prove that $1^3 + 2^3 + ... + n^3 = (1+ 2 + ... + n)^2$
Do you know a simpler expression for $1+2+\ldots+k$? (Once you get the computational details worked out, you can arrange them more neatly than this; I wrote this specifically to suggest a …
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 …
Difference between "≈", "≃", and "≅" - Mathematics Stack Exchange
In mathematical notation, what are the usage differences between the various approximately-equal signs "≈", "≃", and "≅"? The Unicode standard lists all of them inside the Mathematical …
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 …
I have learned that 1/0 is infinity, why isn't it minus infinity?
Generally the only reason one sees 1/0 as infinity is because some systems (incorrectly) output infinity when given dividing by zero.
概率论与数理统计入门 - 知乎
反映了人们对犯第一类错误的最大容忍程度。 ② 置信水平1-α 是显著性水平的对立面，1-α是一个概率值，当α确定时，置信水平随之确定。 置信水平反映的是人们在面对第一类错误时，希望 …