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Mathematics

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Answer score of 25 or more. This badge can be awarded multiple times.
Awarded 14127 times.
What is the probability that a plane through three random points on the surface of the Earth intersects the Moon?
Awarded Sep 20 at 11:12
Integral $\int_{-1}^1\frac1x\sqrt{\frac{1+x}{1-x}}\ln\left(\frac{2\,x^2+2\,x+1}{2\,x^2-2\,x+1}\right) \mathrm dx$
Awarded Sep 18 at 16:28
Norm is weakly lower semicontinuous
Awarded Sep 18 at 11:26
Have I totally misunderstood the Banach–Tarski paradox?
Awarded Sep 17 at 11:50
Proving $\left(1-\frac13+\frac15-\frac17+\cdots\right)^2=\frac38\left(\frac1{1^2}+\frac1{2^2}+\frac1{3^2}+\frac1{4^2}+\cdots\right)$
Awarded Sep 17 at 9:25
Is most of mathematics independent of set theory?
Awarded Sep 17 at 4:47
What would happen if we just made vacuous truths false instead?
Awarded Sep 17 at 0:23
Deep theorem with trivial proof
Awarded Sep 16 at 23:51
Why is $\wedge$ a minimum and $\vee$ a maximum?
Awarded Sep 16 at 19:47
How do I prove that a matrix is a rotation-matrix?
Awarded Sep 16 at 2:22
Why are orthogonal matrices generalizations of rotations and reflections?
Awarded Sep 16 at 2:22
Maximum Likelihood Estimator of parameters of multinomial distribution
Awarded Sep 15 at 5:44
Evaluation of the integral $\int_0^1 \frac{\ln(1 - x)}{1 + x}dx$
Awarded Sep 15 at 3:14
I feel like epsilon-delta is reversed
Awarded Sep 14 at 17:48
What is the probability that $\sum_{k=1}^\infty\left(\prod_{i=1}^ku_i\right)>1$ where $u_i$ are random real numbers in $(0,1)$?
Awarded Sep 14 at 8:00
Is writing $f(z)=u(x,y)+i v(x,y)$ a big abuse of notation in complex analysis?
Awarded Sep 13 at 18:39
$I^2$ does not retract into comb space
Awarded Sep 13 at 2:48
Evaluating $\int_0^1\frac{\ln(x)\ln(1-x)\ln(1+\sqrt{1-x^2})}{x}\mathrm{d}x$
Awarded Sep 12 at 3:34
Show that $\operatorname{rank}(A+B) \leq \operatorname{rank}(A) + \operatorname{rank}(B)$
Awarded Sep 11 at 14:37
How far can one get in analysis without leaving $\mathbb{Q}$?
Awarded Sep 10 at 16:41
How to prove $\int_0^\pi\frac{\ln(2+\cos\phi)}{\sqrt{2+\cos\phi}}d\phi=\frac{\ln3}{\sqrt3}K\left(\sqrt{\frac23}\right)$?
Awarded Sep 9 at 10:04
Show that a locally compact Hausdorff space is regular.
Awarded Sep 8 at 14:12
When is a local homeomorphism a covering map?
Awarded Sep 8 at 13:34
What are morphisms of functors
Awarded Sep 8 at 0:50
What is the relation between analytical Fourier transform and DFT?
Awarded Sep 7 at 15:17
The set of algebraic numbers with odd degrees appears to form a field
Awarded Sep 7 at 10:43
Is $\frac{1}{\alpha} \in \mathbb{Q}[\alpha]$ for irrational $\alpha$?
Awarded Sep 6 at 22:51
Uniqueness of product measure (non $\sigma$-finite case)
Awarded Sep 6 at 17:05
Why is $1^{\infty}$ considered to be an indeterminate form
Awarded Sep 6 at 16:38
Is every compact space locally compact?
Awarded Sep 5 at 23:01
Help with a prime number spiral which turns 90 degrees at each prime
Awarded Sep 5 at 10:49
Why determinant of a 2 by 2 matrix is the area of a parallelogram?
Awarded Sep 5 at 3:19
Is there a continuous function $f:[0,1] \to [0,1$] which passes through every point in its image a finite even number of times?
Awarded Sep 5 at 2:42
Difference between Stokes' Theorem and Divergence Theorem
Awarded Sep 4 at 13:30
What is the largest known prime gap, and why is there so much conflicting information??
Awarded Sep 4 at 11:40
Evaluate $\int_{\frac{1}{2022}}^{2022}\frac{1+x^{2}}{x^2+x^{2022}}dx$
Awarded Sep 3 at 18:05
What is the difference between necessary and sufficient conditions?
Awarded Sep 3 at 17:40
Why does 'The King Property' of integration work?
Awarded Sep 2 at 0:23
prove $RP^3\cong SO(3)$
Awarded Sep 2 at 0:23
Show $f$ is constant if $|f(x)-f(y)|\leq (x-y)^2$.
Awarded Aug 31 at 23:01
How to get to the formula for the sum of squares of first n numbers?
Awarded Aug 31 at 15:06
Why does the Dedekind Cut work well enough to define the Reals?
Awarded Aug 31 at 6:28
Is there a law that you can add or multiply to both sides of an equation?
Awarded Aug 31 at 1:35
Is there a law that you can add or multiply to both sides of an equation?
Awarded Aug 31 at 1:35
Maclaurin expansion of $\arcsin x$
Awarded Aug 30 at 19:37
Maclaurin expansion of $\arcsin x$
Awarded Aug 30 at 19:37
When is $2$ a quadratic residue mod $p$?
Awarded Aug 29 at 6:17
How do ordinals manage to descend finitely?
Awarded Aug 28 at 10:56
The $5n+1$ Problem
Awarded Aug 28 at 8:39
Prove or disprove: If $\sum a_n$ converges conditionally, then $\sum n^2 a_n$ diverges
Awarded Aug 27 at 22:06
Counterexample to "Measurable in each variable separately implies measurable"
Awarded Aug 27 at 9:17
What's the motivation of the definition of primary ideals?
Awarded Aug 25 at 21:42
Why this approximation for $\pi$ is so accurate?
Awarded Aug 25 at 13:32
Is the weak topology sequential on some infinite-dimensional Banach space?
Awarded Aug 25 at 9:19
Details of gluing sheaves on a cover
Awarded Aug 24 at 14:03
Union of connected subsets is connected if intersection is nonempty
Awarded Aug 24 at 9:05
What is lag in a time series?
Awarded Aug 23 at 18:17
Can the notion of "squaring" be extended to other shapes?
Awarded Aug 23 at 1:37
Why can't the second fundamental theorem of calculus be proved in just two lines?
Awarded Aug 21 at 16:51
How can the $SU(2)$ group have a $3$-dimensional representation?
Awarded Aug 20 at 12:06
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