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.

12848 questions
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What does ∗⇒mean?

I am still really new to mathematical notations, and I am still having difficulty understanding most of the languages and notations. A recent notation I am very confused about is:$\def\starrow{\stackrel\ast\Rightarrow}\starrow$ . I found that ⇒…
WCGPR0
  • 171
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Where could (do?) we go after exhausting greek letters?

I'm still in high school but after all my various math and science classes including calculus, statistics, geometry, and physics, I think that we've pretty much run the course of both upper and lower standard letters, and upper and lower greek…
Bassinator
  • 425
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Meaning of function mapping notation $d: X \times X \to \mathscr{R}$

I am trying to do some self-studying and am consistently getting bogged down by sophisticated mathematical notation. For example, something simple like this in a book: Let $X$ be a non empty set and then we define a metric $d$ on X as the…
Luca
  • 513
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4 answers

Symbol for 'When ...'

I have never found one listed anywhere: Is there a symbol for a 'when' condition (example below). $A=B$ when $A$ is even
CobaltHex
  • 173
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3 answers

Is it proper to write $\int \partial x$

For single variable function, you write $\int dx$ But for multivariable function, can you write $\int \partial x$?? I've never seen the latter, can someone explain why?
Fraïssé
  • 11,275
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3 answers

What is the amalg symbol?

I saw this formula: $A \amalg B$, where $A$ and $B$ are sets. I searched for the name of the symbol, "amalg", but haven't found a definition. What is the meaning of this symbol?
Erel Segal-Halevi
  • 10,555
6
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2 answers

What does the colon in the statement $T:t\to−t$ mean?

I don't understand what the colon $T:t\to−t$ means. I understand that it does something, is it a variable or just a symbol that has no significance?
user46919
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2 answers

What is the math notation for this type of function?

A function that turns a real number into another real number can be represented like $f : \mathbb{R}\to \mathbb{R}$ What is the analogous way to represent a function that turns an unordered pair of elements of positive integers each in $\{1,...,n\}$…
opt
  • 1,114
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Why do we use lowercase $k$ for fields?

As a general rule in mathematical notation, structures and collections are given uppercase names, while elements often have lowercase names. However, it's not uncommon for a field to be called $k$ (for example in this question). I know that this…
Max
  • 386
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4 answers

What is ≡ operator used for in math?

Possible Duplicate: When should I use $=$ and $\equiv$? I heard about this in our calculus class years ago. I was actually not in that class when the professor explained this. 95% of engineering student do not know about this operator. I'm trying…
TheTechGuy
  • 271
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What does the long curly line mean?

Sorry to sound incredibly ignorant, but I am...at least in math anyway. What does this symbol: $\int$ mean?
david
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Should I use parentheses when writing $\log$?

Should I be using parentheses when using things like $\log$ in LaTeX, and when handwriting? Should I use $\log x$ or $\log(x)$? If it's just one value or variable, I can see getting away with not using parentheses, but suppose I have a function in…
polemon
  • 1,041
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3 answers

Does "iff" mean "if and only if" $(\Longleftrightarrow)$?

Sometimes I do read in a sentence: some statement iff another statement At first I thought it is a mispelling, but then I realized, that I do encounter this at many different posts. Does this mean equivalence?
Aufwind
  • 2,215
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Is MDCDXXXIV a correct roman numeral?

A building near my workplace has a very large carved inscription: $MDCDXXXIV$ As it looks like roman numeral, I was trying to see what year it was meant to represent. Logically, I'd think it's 1934, but it should be written $MCMXXXIV$. Is $MDCD$ a…
SteeveDroz
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