Mathematics

25%

+0 −4

If a changes to b, then doesn't a + d = b? Why a(1 + d) = b? [closed]

0 answers · posted 4d ago by Chgg Clou‭ · closed 2d ago by Peter Taylor‭

high-school-mathematics

25%

+0 −4

Isn't Ontario 49 always worse than Daily Grand? [closed]

0 answers · posted 10d ago by Chgg Clou‭ · closed 2d ago by Peter Taylor‭

lottery

60%

+1 −0

The meaning of $\pm$

2 answers · posted 4d ago by tommi‭ · last activity 3d ago by Derek Elkins‭

notation

22%

+0 −5

At what jackpot minimum is playing Lottario rational?

1 answer · posted 10d ago by Chgg Clou‭ · edited 4d ago by Chgg Clou‭

lottery

22%

+0 −5

How can school children intuit why over 100, D is larger? But under 100, D% is larger?

0 answers · posted 4d ago by Chgg Clou‭ · edited 4d ago by Chgg Clou‭

high-school-mathematics

60%

+1 −0

Connection between caustics and conjugate points?

0 answers · posted 1mo ago by tommi‭

differential-geometry

66%

+2 −0

Unification and generalization of limit and colimit

1 answer · posted 1mo ago by celtschk‭ · last activity 1mo ago by Derek Elkins‭

limits category-theory

75%

+4 −0

Generalization of categorical product

1 answer · posted 1mo ago by r~~‭ · last activity 1mo ago by Derek Elkins‭

category-theory

50%

+0 −0

Universal property of quotient spaces

1 answer · posted 2mo ago by Snoopy‭ · last activity 2mo ago by Snoopy‭

topology

71%

+3 −0

Criterion in terms of the bases for determining whether one topology is finer than another

1 answer · posted 2mo ago by Snoopy‭ · last activity 2mo ago by celtschk‭

topology

50%

+3 −3

Is it worth it to replace Arabic numerals with Kaktovik numerals?

1 answer · posted 3mo ago by GoldenGold‭ · last activity 2mo ago by DavidCary‭

Kaktovik numerals

50%

+0 −0

Finding a quadratic that has solutions to given values

1 answer · posted 2mo ago by brah‭ · last activity 2mo ago by trichoplax‭

algorithm approximation numerical-analysis

71%

+3 −0

What is the probability that the convex hull of $n$ randomly distributed points has $l$ of the points on its boundary?

1 answer · posted 4mo ago by siric‭ · edited 2mo ago by tommi‭

probability convex-hull

71%

+3 −0

Prove that 49 is the only prime square to be followed by twice a prime square and then a semiprime

0 answers · posted 2mo ago by Peter Taylor‭ · edited 2mo ago by Peter Taylor‭

number-theory integer-sequences

77%

+5 −0

Is $f(x)=\sin(x)$ the unique function satisfying $f'(0)=1$ and $f^{(n)}(\Bbb R)\subset [-1,1]$ for all $n=0,1,\ldots$?

1 answer · posted 7mo ago by Grove‭ · edited 2mo ago by Pavel Kocourek‭

derivatives real-analysis

60%

+1 −0

Is there a "regular" quasi-convex function $f:\Bbb R^2 \to \Bbb R$ that is not a monotone transformation of any convex function?

0 answers · posted 2mo ago by Pavel Kocourek‭

multivariable-calculus real-analysis convex-analysis monotone-functions

60%

+1 −0

Is there a two variable quartic polynomial with two strict local minima and no other critical point?

0 answers · posted 2mo ago by Pavel Kocourek‭

multivariable-calculus real-analysis maxima-minima polynomials roots

30%

+1 −5

What did James Stewart mean by "the line integral reduces to an ordinary single integral in this case" ?

2 answers · posted 3mo ago by TextKit‭ · edited 2mo ago by trichoplax‭

line-integral

66%

+2 −0

Proving $|{\bf R}^{\bf R}|=|2^{\bf R}|$ using the Schroeder-Bernstein Theorem

2 answers · posted 2mo ago by Snoopy‭ · last activity 2mo ago by celtschk‭

set-theory

28%

+0 −3

Expanding the Integration problem.

1 answer · posted 3mo ago by Anonymous‭ · last activity 3mo ago by TextKit‭

integration

77%

+5 −0

What is the Name of Function for Probability of a Certain Sum on Random Die Rolls?

1 answer · posted 3mo ago by James McLellan‭ · last activity 3mo ago by Derek Elkins‭

statistics

37%

+1 −3

Find all integer solutions for $a_1(a_1+k)(a_1+2k)...(a_1+(2k+1)d)+1 = n^2$ [closed]

1 answer · posted 4mo ago by beloh‭ · edited 3mo ago by beloh‭

arithmetic algebra series

60%

+1 −0

Dividing a cuboid in four

1 answer · posted 3mo ago by Yair Rand‭ · last activity 3mo ago by Peter Taylor‭

geometry

66%

+2 −0

Example of $f:[0,1]\to\mathbf{R}$ with $\lim_{a\to 0^+}\int_a^1f(x)dx=L $ for some real number $L$ but $\int_0^1|f(x)|dx=\infty $

1 answer · posted 4mo ago by Snoopy‭ · last activity 4mo ago by r~~‭

real-analysis improper-integral

71%

+3 −0

Finding the limit $ \lim_{x\to 0^+}e^{1/x}\sum_{n=\lfloor 1/x\rfloor}^\infty\frac{x^n}{n} $

1 answer · posted 4mo ago by Snoopy‭ · last activity 4mo ago by r~~‭

real-analysis limits

71%

+3 −0

Given two angles of a triangle, finding an angle formed by a median

1 answer · posted 7mo ago by Snoopy‭ · last activity 4mo ago by Tim Pederick‭

euclidean-geometry vector

75%

+4 −0

Is this formula for the minimal sum correct?

1 answer · posted 5mo ago by celtschk‭ · last activity 5mo ago by celtschk‭

set-theory ordinal-numbers

71%

+3 −0

Do linear and group invariant functions allowed to go inside(?) integral operators?

1 answer · posted 5mo ago by sepiabrown‭ · last activity 5mo ago by r~~‭

integration geometric-deep-learning invariant-function

14%

+0 −10

How can 3/1 ≡ 1/(1/3), when left side features merely integers, but right side features a repetend?

2 answers · posted 6mo ago by Chgg Clou‭ · last activity 6mo ago by Snoopy‭

arithmetical-hierarchy

77%

+5 −0

Does there exist a non-zero game such that the sum of three or more copies of it is zero?

0 answers · posted 6mo ago by celtschk‭

combinatorial-game-theory

77%

+5 −0

Why can't we conclude the extrema property of a function from its quadratic approximation when the discriminant is zero?

1 answer · posted 6mo ago by Snoopy‭ · last activity 6mo ago by Snoopy‭

multivariable-calculus derivatives

71%

+3 −0

How to calculate remaining volume of a wire spool

2 answers · posted 6mo ago by re89j‭ · last activity 6mo ago by Olin Lathrop‭

geometry volume

28%

+0 −3

What's wrong with evaluating $n(n-1) \dots (n-[k-3])(n-[k-2])\color{red}{(n-[k-1])}$ at $k = 1$?

1 answer · posted 1y ago by DNB‭ · edited 6mo ago by Peter Taylor‭

notation

75%

+4 −0

Product of empty set of elements vs. product over empty indexing set — is there any difference?

1 answer · posted 2y ago by The Amplitwist‭ · edited 6mo ago by Peter Taylor‭

product definition notation algebra

71%

+3 −0

Finding distance to parabola's focus, given some points

1 answer · posted 1y ago by msh210‭ · edited 6mo ago by Peter Taylor‭

geometry conics

71%

+3 −0

Show that $\forall n \in \mathbb{Z}^{+}$, $25^n \equiv 25 \bmod{100}$.

2 answers · posted 6mo ago by Carefree Explorer‭ · edited 6mo ago by Peter Taylor‭

number-theory recreational-mathematics modular-arithmetic

75%

+4 −0

Proving that $p\mid (p+1776)$ if $p$ is a prime and $p(p+1776)$ is a perfect square

2 answers · posted 6mo ago by Snoopy‭ · last activity 6mo ago by Snoopy‭

number-theory algebra

71%

+3 −0

organizing a library

1 answer · posted 6mo ago by msh210‭ · last activity 6mo ago by celtschk‭

combinatorics recreational-mathematics

75%

+4 −0

If $\mathbf{R}$ is thought of as a vector space over $\mathbf{Q}$, what is its dimension?

1 answer · posted 7mo ago by Snoopy‭ · last activity 7mo ago by r~~‭

linear-algebra vector-space

33%

+0 −2

Inhomogenous differential equations in sciences

0 answers · posted 7mo ago by MissMulan‭ · edited 7mo ago by MissMulan‭

calculus equation differential applied-mathematics

71%

+3 −0

Prove $e^x \ge x+1 \\\; \forall x \in \mathbb{R}$ using induction

1 answer · posted 7mo ago by Carefree Explorer‭ · edited 7mo ago by Derek Elkins‭

limits induction inequality solution-verification

50%

+0 −0

Is there a way to encode a unique arrangement of vertices of a graph with a unique short word?

2 answers · posted 8mo ago by Carefree Explorer‭ · last activity 7mo ago by celtschk‭

graph-theory

71%

+3 −0

Show that $f(x) = \arctan\left(\frac{x}{x+1}\right) + \arctan\left(\frac{x+1}{x}\right) = \frac{\pi}{2}$

2 answers · posted 8mo ago by Carefree Explorer‭ · last activity 8mo ago by Derek Elkins‭

limits trigonometry

60%

+1 −0

What's the common ratio for this geometric sequence?

1 answer · posted 8mo ago by General Sebast1an‭ · last activity 8mo ago by tommi‭

geometric-sequence sequence

71%

+3 −0

The gcd of powers in a gcd domain

0 answers · posted 8mo ago by Snoopy‭ · edited 8mo ago by Snoopy‭

abstract-algebra

44%

+2 −3

Isn't "any, some, or all" redundant? Why not write just "any"?

1 answer · posted 8mo ago by Chgg Clou‭ · last activity 8mo ago by Tim Pederick‭

terminology

50%

+0 −0

What are the 2 arithmetic means of $x + y$ and $4x - 2y$?

2 answers · posted 9mo ago by General Sebast1an‭ · last activity 9mo ago by General Sebast1an‭

arithmetic sequence mean

71%

+3 −0

Notation for nested exponents

1 answer · posted 9mo ago by JRN‭ · last activity 9mo ago by leovt‭

notation exponents

70%

+5 −1

equilateral triangle inscribed in an ellipse

2 answers · posted 1y ago by msh210‭ · last activity 9mo ago by Anonymous‭

conics triangle

71%

+3 −0

Do the Faber partition polynomials have integer coefficients?

1 answer · posted 9mo ago by Peter Taylor‭ · last activity 9mo ago by Peter Taylor‭

combinatorics generating-functions polynomials

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