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.
12,981
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How to denote domain and range of a function that substitutes a given interval?
I neeed to denote the range and domain of a function that subsitutes a given interval with a diffirent interval.
For example: $f ([x,y]) = [x, x + \frac{y-x}{2}]$
My thoughts were $f: [0,1] \...
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Does tetration go up or down? (and other related questions) [duplicate]
Tetration is defined as “repeated exponentiation” - that is, $2$ tetrated to $5$ is equal to $2^{2^{2^{2^2}}}$, just as $2$ exponentiated to $5$ is equal to $2\cdot{2}\cdot{2}\cdot{2}\cdot{2}$ (...
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On the definition of parameter dependent integral function
I have the following theorem about parameter dependent integral function.
Thm. Let $(X,\mathcal{M})$ a measurable space, $\mu:\mathcal{M} \to [0,+\infty]$ a positive measure, $(Y,\tau)$ a first ...
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What does this the curly brace mean in an integral [closed]
I have seen the following integral given in an answer to one of my questions:
$$
\int_{z_0}^1 \int_0^1 1\left\{y \le \dfrac{z_0}{x}\right\}dydx
$$
What do the curl braces mean in this context?
...
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Question on notation in Extremal Combinatorics
In the following image, can someone please explain in detail the meaning of the $\sum$*(n,k) for me? I don't really see why the author mentions the following:
1.) What is the significance of whether $...
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1
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Does the Wedge Operator (^) have some meaning in Linear Programming?
I'm reading about the Cassowary algorithm - it's an iterative algorithm which draws heavily on the simplex algorithm and Linear Programming.
While reading the paper, I keep encountering the wedge ...
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1
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Why is $\frac{p}{-q}$ written as $\frac{-p}{q}$ and not as $\frac{p}{-q}$?
I have seen in a pure mathematics book by G.H Hardy that $\frac{-p}{q}$ is equal to $\frac{p}{-q}$, but why it is taken as that why not substitute the whole equation as $\frac{p}{-q}$, also if a ...
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Notation: why $f_\lambda$ in the hook-length formula? [closed]
I just learned the hook-length formula: the number of Standard Young Tableaux of size $n$ and shape $\lambda$ is
$$\frac{n!}{\prod_\limits{x} \operatorname{hook}(x)}$$
where the product runs over all ...
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5
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Is an infinite composition of bijections always a bijection?
Main Question
Suppose I have a sequence of real valued functions $f_1:X_0\rightarrow X_1,...,f_n:X_{n-1} \rightarrow X_n,...,$ and I then, with $\circ$ denoting function composition, define
$$g_n : ...
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Ravi Vakil's jigsaw notation of quotient groups - can it be used to "geometrically" prove theorems?
I just discovered this: Puzzling through exact sequences, a picture book when I'm learning abstract algebra.
This thing astonishes me - it demonstrates a lot of isomorphism theorems with only jigsaw ...
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Meaning of asterisk (*) in the context of hypothesis spaces
Unfortunately, the asterisk notation in a superscript (*) is used differently in many contexts, e.g., conjugate transpose, Kleene star, optimal argument. This makes the asterisk difficult to ...
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2
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Could it make sense to think of 0, -1, and i as overloaded unary operators rather than numbers?
This thought occurred to me and I was wondering if anyone had explored it.
For example, -x = (-1)*x. We could (choosing arbitrary symbols) rewrite this as ...
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Is there a standard notation for complementary and supplementary angles?
I recently was trying to solve a complex geometric problem using trigonometry and it made me wonder - is there a standard out there for annotating supplementary and complementary angles? I want to be ...
4
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1
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Name for a "functor" that does not preserve identities.
The definition of a functor $F$ between two categories $\mathcal{C}$ and $\mathcal{D}$ says that:
If $f$ is a morphism between objects $A,B \in \mathcal{C}$ then $F(f)$ is a morphism between $F(A),F(...
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Question about the seemingly different meaning of the notation $(x)$ in $k[x]$ and $k[x,y]$ [duplicate]
Background
Example: If $k$ is a field, the ideal $(x)$ is maximal in $k[x]$. In $k[x,y]$, the ideal $(x)$ is not maximal, the ideal $(x,y)$ is maximal. We have $(x)\subseteq (x,y)\subseteq k[x,y]$.
...