Mathematics Stack Exchange
Mathematics Stack Exchange

Questions tagged [notation]

Questions on the meaning, history, and usage of mathematical symbols and notation. Please remember to mention where (book, paper, webpage, etc.) you encountered any mathematical notation you are asking about.

Before asking a question on the site, please check if you can find your answer in Earliest Uses of Various Mathematical Symbols or the book A History of Mathematical Notations.

Alternatively, a textbook or paper usually takes the time to explain the notation they're using; please remember to mention where you've seen the notation you are asking about.

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What is the meaning of the math symbol $\because$?

This is essentially a $\therefore$ symbol upside down, and I have seen it in some proofs, not many. What does it mean?
K Split X
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3 answers

What does the letter epsilon signify in mathematics?

This letter "$\varepsilon$" is called epsilon right ? What does it signify in mathematics ?
Geek
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What is the symbol $\triangleq$?

I came across this new symbol while reading a document about writing proofs, and I have never seen it before.
Mirrana
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3 answers

What is the mathematical symbol for range?

An unsophisticated question from a neophyte: Given the numbers: $1,2,3,4,5$ What is the symbol for the range of the numbers? i.e. the lowest-highest number in the set. For example, the min max is $1-5$. The ____ is $1-5$. (insert math symbol…
Minnow
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When should I use $=$ and $\equiv$?

In what context should I use $=$ and $\equiv$? What is the precise difference? Thanks! (I wasn't sure what to tag this with, any suggestions?)
Danny King
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6 answers

Is there a mathematical symbol for "For every element"?

Is there a mathematical symbol that means "For every element"? I want the meaning to have similar function as an iteration, say for loop.
drum
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What symbol expresses “less than approximately”?

Suppose, I want to state that $a$ is less than $b$. However, I do not know $b$ exactly, but only that it is approximately $c$. With other words I want to state that $a$ is less than some value that is approximately $c$. I want to express this using…
Wrzlprmft
  • 5,718
26
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2 answers

Why is $\wedge$ a minimum and $\vee$ a maximum?

Why does $\wedge$ denote a minimum and $\vee$ a maximum? Where did this notation come from? I keep getting them mixed up because to me, $\wedge$ should be a maximum: it's a hill, or a curve reaching its maximum. Similarly, $\vee$ is a gulf, or a…
James
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What's the correct notation for log squared?

I ran across these two notations for the log function (squared), which one is more conventional. $\log^2(n)$ or $[\log(n)]^2$
Roronoa Zoro
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Why are symbols not written in words?

We could have written = as "equals", + as "plus", $\exists$ as "thereExists" and so on. Supplemented with some brackets everything would be just as precise. $$\exists x,y,z,n \in \mathbb{N}: n>2 \land x^n+y^n=z^n$$ could equally be written…
zooby
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Why is union sign not allowed to denote intervals of function increasing?

On the calculus exam, we were given a function $$f(x) = \frac{2x^2+x-1}{x^2-1} $$ and asked to find intervals of function increasing and decreasing. In the post-exam solutions PDF, it was written that f(x) is increasing on $$(-\infty; -1), (-1; 1),…
Rafael Sofi-zada
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What does sgn mean?

I am reading "space filling curve" by Hans Sagan. On page 17, on equation (2.3.11) in the equation, a function sgn is used. What is sgn? To put it into context, in the book it says $h_n=$sgn$(n)[(n-1)+i]$
Al jabra
  • 2,331
22
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What does this symbol mean? (looks like a 1 with double vertical line)

I'm studying a course on probability and statistics and at some point this symbol comes up without introduction. It looks like the number one, but slightly bigger and with a double vertical line. First time it comes up is when discussing…
Yoh
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What does the $\prod$ symbol mean?

This is one of those cases where I would google if I could, but I don't know what to search for. I've come across this symbol a few times, but I have no clue what it means or what it is called. $$\prod$$ Furthermore, what are the $\coprod$ and…
NictraSavios
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How do I understand the meaning of the phrase "up to~" in mathematics?

I am reading a book that explains elementary number theory: Number Theory: A Lively Introduction with Proofs, Applications, and Stories by James Pommersheim, Tim Marks and Erica Flapan. The authors say, "We express this idea in the statement of…
MS.Kim
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