Mathematics

81%

+7 −0

Endomorphisms on an entropic structure whose pointwise product is the identity automorphism - entropic idempotent structure?

0 answers · posted 10mo ago by Prime Mover‭ · edited 10mo ago by Prime Mover‭

abstract-algebra

30%

+1 −5

In "if and only if" proofs, why's 1 direction easier to prove than the other?

2 answers · posted 2y ago by Chgg Clou‭ · last activity 10mo ago by Prime Mover‭

logic

75%

+4 −0

Optimising a 3 value problem (well 2 really)

1 answer · posted 10mo ago by KalleMP‭ · last activity 10mo ago by Peter Taylor‭

analysis formula algorithm

66%

+2 −0

Notation for one-sided hypothesis testing

0 answers · posted 10mo ago by tommi‭

statistics notation hypothesis-testing

83%

+8 −0

Complex numbers in 2D, quaternions in 4D, why nothing in 3D?

2 answers · posted 12mo ago by Fred Wamsley‭ · last activity 10mo ago by Derek Elkins‭

quaternions

60%

+1 −0

How $ijk=\sqrt{1}$?

2 answers · posted 1y ago by deleted user · last activity 10mo ago by Tim Pederick‭

quaternions

80%

+6 −0

$g(x)\xrightarrow{x\to\infty}\infty$ Implies $g'(x)\leq g^{1+\varepsilon}(x)$

3 answers · posted 11mo ago by Udi Fogiel‭ · last activity 10mo ago by Peter Taylor‭

calculus

60%

+1 −0

Are vectrices useful for calculations as opposed to formalism?

1 answer · posted 10mo ago by Fred Wamsley‭ · last activity 10mo ago by Derek Elkins‭

Vectrix Numerical

33%

+0 −2

How to intuit p = Calvin's probability of winning each game independently = $1/2 \implies$ P(Calvin wins the match) = 1/2?

1 answer · posted 1y ago by DNB‭ · last activity 11mo ago by viäränlaenen‭

probability

71%

+3 −0

Matrices with rotational symmetry

1 answer · posted 11mo ago by Peter Taylor‭ · last activity 11mo ago by Peter Taylor‭

linear-algebra matrices

50%

+0 −0

Why does the Dottie number $=\sqrt{1-\left(2\text I^{-1}_\frac12\left(\frac12,\frac32\right)-1\right)^2}$?

0 answers · posted 11mo ago by Tyma Gaidash‭ · edited 11mo ago by Tyma Gaidash‭

probability equation median inverse

50%

+0 −0

A discrete-time queue Markov Chain problem

0 answers · posted 12mo ago by Joe‭

Markov-chains

50%

+0 −0

How can I justify whether I'm able to apply the Gaussian elimination method to this system?

1 answer · posted 1y ago by dumplings‭ · edited 1y ago by Peter Taylor‭

equation system gaussian

50%

+0 −0

Sample skewness consistency [closed]

0 answers · posted 1y ago by Guilherme Costa‭ · closed 1y ago by Peter Taylor‭

skewness statistics

33%

+0 −2

Why 1. multiply the number of independent options? 2. add the number of exclusive options?

3 answers · posted 1y ago by DNB‭ · last activity 1y ago by Tim Pederick‭

probability

71%

+3 −0

Maximize Independent Variable of Matrix Multiplication

1 answer · posted 1y ago by Josh Hyatt‭ · edited 1y ago by Josh Hyatt‭

matrices vector

75%

+4 −0

Is it impossible to prove Jensen's inequality by way of step functions?

1 answer · posted 1y ago by whybecause‭ · last activity 1y ago by whybecause‭

real-analysis convex-analysis Jensen's-inequality

71%

+3 −0

"Pointwise equicontinuity implies uniform" implies compact

1 answer · posted 1y ago by whybecause‭ · last activity 1y ago by whybecause‭

real-analysis equicontinuity continuity metric-spaces

33%

+0 −2

How to intuit, construe multiplicands and multiplicators $\le 10$ resulting from $\dbinom pc$, WITHOUT division or factorials? [duplicate]

0 answers · posted 1y ago by DNB‭ · edited 1y ago by DNB‭

combinatorics

60%

+1 −0

$\{f_n\}\to f$ in $X$ implies $||f||\le\liminf||f_n||$

1 answer · posted 1y ago by whybecause‭ · last activity 1y ago by whybecause‭

real-analysis functionals normed-vector-space

75%

+4 −0

Missing a solution: Are A and B always equal if A-B=0

3 answers · posted 1y ago by re89j‭ · last activity 1y ago by tommi‭

logic equation algebra problem

33%

+0 −2

Out of 4 people, why does ways to choose a 2-person committee overcount by 2 the ways to divide the 4 into 2 teams of 2?

1 answer · posted 1y ago by DNB‭ · last activity 1y ago by Tim Pederick‭

probability

33%

+1 −4

How can you "easily see that such squares [of side length $\sqrt{13}$ and $\sqrt{18}$] will not fit into the [4 × 4] grid"?

1 answer · posted 1y ago by DNB‭ · last activity 1y ago by Tim Pederick‭

geometry

40%

+0 −1

How can a 15 year old construe the LHS of Generalized Vandermonde's Identity, when it lacks summation limits and a summation index?

2 answers · posted 1y ago by DNB‭ · last activity 1y ago by r~~‭

summation

40%

+0 −1

To correct for overcounting, why can't we divide by the sum of the over-counts? [duplicate]

0 answers · posted 1y ago by DNB‭ · closed as duplicate 1y ago by Peter Taylor‭

combinatorics

33%

+0 −2

Why's Pr(the running total of a fair dice rolled repeatedly = n) = $\frac16 (p_{n-1} + p_{n-2} + p_{n-3} + p_{n-4} + p_{n-5} + p_{n-6})$?

0 answers · posted 1y ago by DNB‭ · edited 1y ago by DNB‭

probability

40%

+0 −1

Why's a 2-player game with "win by two" rule = Gambler's Ruin where each player starts with $2? Why N = 4?

0 answers · posted 1y ago by DNB‭ · edited 1y ago by DNB‭

probability

60%

+1 −0

How's it possible to arrange 0 objects? How can 0! = 1?

3 answers · posted 1y ago by DNB‭ · edited 1y ago by Quintec‭

combinatorics

40%

+0 −1

If C = Calvin wins the match, and $X \thicksim Bin(2, p) =$ how many of the first 2 games he wins — then why P(C|X = 1) = P(C)?

1 answer · posted 1y ago by DNB‭ · last activity 1y ago by Peter Taylor‭

probability

28%

+0 −3

How can you analogize mathematical induction to dominoes falling, if some domino can fail to topple? [closed]

1 answer · posted 1y ago by Chgg Clou‭ · closed 1y ago by Peter Taylor‭

induction

50%

+0 −0

How can I re-write or supplant “basis point” UNambiguously?

0 answers · posted 2y ago by Chgg Clou‭ · edited 1y ago by Chgg Clou‭

percentage

50%

+1 −1

How to deduce which ETF is redundant? a of ETF1's holdings in ETF3, a of ETF2 in ETF3, b of ETF1 are in ETF2, b of ETF2 in ETF1.

0 answers · posted 1y ago by Chgg Clou‭ · edited 1y ago by Chgg Clou‭

finance

71%

+3 −0

Are we in a "history-valley" for Topology?

2 answers · posted 1y ago by whybecause‭ · last activity 1y ago by Derek Elkins‭

topology history-philosophy-of-math

33%

+0 −2

Intuitively, why does $p$ vary inversely with $P(C_3 \mid D_2)$? But directly with $P(C_2 \mid D_3)$?

1 answer · posted 1y ago by DNB‭ · last activity 1y ago by whybecause‭

probability

50%

+0 −0

"the people who move have a percentage of Democrats which is between these two values" — How does this furnish intuition for Simpson's Paradox?

0 answers · posted 1y ago by DNB‭ · edited 1y ago by DNB‭

probability

33%

+0 −2

For (a variation) of the Monty Hall problem, what permits you to repaint doors 2 and 3? What permits you to replace p with $1 - p$?

0 answers · posted 1y ago by DNB‭ · edited 1y ago by DNB‭

probability

33%

+0 −2

Intuitively, why can $a, b$ cycle in ${\color{red}{b}} = \frac c{\color{red}{a}} \iff {\color{red}{a}} = \frac c{\color{red}{b}}$?

3 answers · posted 1y ago by Chgg Clou‭ · last activity 1y ago by whybecause‭

arithmetic

75%

+4 −0

$\int_{E_n} |g|^q = \left| \int_E \chi_{E_n}\cdot \text{sgn}(g)\cdot g \cdot |g|^{q-1}\cdot |g| \right|$

0 answers · posted 1y ago by whybecause‭ · edited 1y ago by Derek Elkins‭

real-analysis Lp-space

28%

+0 −3

Without calculations, how can you visualize "that half the squares are white and half are black"?

1 answer · posted 1y ago by DNB‭ · last activity 1y ago by whybecause‭

probability

50%

+1 −1

In general, does $\color{forestgreen}{P(A|M)} + \color{red}{P(B|M)} = 1$?

1 answer · posted 1y ago by DNB‭ · last activity 1y ago by whybecause‭

probability

50%

+1 −1

Acceptable, usual to write $\ge 2$ pipes simultaneously?

1 answer · posted 1y ago by DNB‭ · last activity 1y ago by Derek Elkins‭

probability

50%

+0 −0

How does $P(C > D \mid C = 2) \neq P(C > D \mid C \neq 2)$ prove that B > C depends on C > D?

0 answers · posted 1y ago by DNB‭ · edited 1y ago by DNB‭

probability

71%

+3 −0

Is Pythagorean theorem really valid in higher dimensional space?

2 answers · posted 1y ago by deleted user · edited 1y ago by zavier‭

pythagoras right-triangle

33%

+0 −2

Is Mathematical Induction truly "induction", or misnamed? [closed]

3 answers · posted 1y ago by Chgg Clou‭ · closed 1y ago by Peter Taylor‭

induction

33%

+0 −2

How do mathematicians measure area for points?

1 answer · posted 1y ago by deleted user · last activity 1y ago by zavier‭

geometry area point border perimeter

40%

+0 −1

Why must percent change divide the difference by the old, NOT new, value?

1 answer · posted 1y ago by Chgg Clou‭ · last activity 1y ago by celtschk‭

percentage

60%

+1 −0

If a matrix has lots of values in a column but, not in row than, what that actually called?

1 answer · posted 1y ago by deleted user · last activity 1y ago by 4015.alt‭

linear-algebra matrices

60%

+1 −0

What does upper indices represent?

2 answers · posted 1y ago by deleted user · last activity 1y ago by r~~‭

notation tensors

50%

+0 −0

What is the parallel for edges?

1 answer · posted 1y ago by deleted user · last activity 1y ago by r~~‭

geometry terminology

33%

+2 −6

Can we add without using addition?

3 answers · posted 1y ago by General Sebast1an‭ · last activity 1y ago by DavidCary‭

equation arithmetic

Communities