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Evaluate $\iiint_{[0,1]^3}\frac{dx\,dy\,dz}{(1+x^2+y^2+z^2)^2}$

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Anonymous

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Uniqueness of the maximizer of the Hardy inequality

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Giuseppe Negro

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The vertices of a hexagon are random points on a unit circle; $a,b,c$ are the lengths of three random sides. Conjecture: $P(ab<c)=\frac35$.

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Dan

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Finite Sets, Equal Cardinality, Injective $\iff$ Surjective.

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JacobCheverie

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Sharper Lower Bounds for Binomial/Chernoff Tails

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Thomas Ahle

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Finding a property that is true for every left ideal but not for right ideals

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Eduardo Magalhães

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Intuition of non-concretizable categories?

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user56834

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Octonionic formula for the ternary eight-dimensional cross product

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anon

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Can every natural number be written as a sum of signed odd squares?

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Descartes Before the Horse

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$f(n)$ is the number of groups of order $n$. $f(a)\cdot f(b)\leq f(a\cdot b)$?

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Jorge Rael

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Direct product vs direct sum of infinite dimensional vector spaces?

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wanderingmathematician

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Maximum value of $f(x) = \cos x \left( \sin x + \sqrt {\sin^2x +\sin^2a}\right)$

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Ananya

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Number of subgroups of an infinite group

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In78

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All Etale morphisms $X\to\Bbb A^1$

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Earth Cracks

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Difference between parentheses and angle brackets in vector notation

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user5826

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What branch of math studies proving $g(\mathbf x) \leq g(\sigma \cdot \mathbf x)$ results?

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Mehdi Jafarnia Jahromi

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Complex keyhole contour integral

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hhattiecc

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When is a group isomorphic to a proper subgroup of itself?

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user231200

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What is a "category"? [closed]

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Stan Shunpike

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Infinite Series -: $\psi(s)=\psi(0)+\psi_1(0)s+\psi_2(0)\frac{s^2}{2!}+\psi_3(0)\frac{s^3}{3!}+.+.+ $.

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Nirvana

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New norm with strictly coarser induced topolgy

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Claire

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Expectation of quotient of random variables

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user128422

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Prove that ${e\over {\pi}}\lt{\sqrt3\over{2}}$ without using a calculator.

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JV.Stalker

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Exponential distribution unbiased estimator

Awarded Apr 13 at 18:26

georgmierau

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Book recommendations for Combinatorics for Computer Science Students

Awarded Apr 13 at 17:26

Abdelrhman Sersawy

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Stereographic projection (Theorem that circles on the sphere get mapped to circles on the plane)

Awarded Apr 13 at 14:32

Kevin

3772 silver badges9 bronze badges

Riemann Zeta Function's Analytic Continuation

Awarded Apr 13 at 12:34

MathGuy

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Division algorithm for polynomials in R[x], where R is a commutative ring with unity.

Awarded Apr 13 at 9:48

tony

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Can a function have partial derivatives, be continuous but not be differentiable?

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lotus57

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Number raised to power of irrational number

Awarded Apr 12 at 15:05

Bharath

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non-vanishing k-form on a k-manifold in $\mathbb{R}^n$ implies orientability

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Enzo

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Topological idea of orientability of manifold

Awarded Apr 12 at 10:36

Anubhav Mukherjee

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How to prove that $x^{1-x}+(1-x)^{x}\leq x^{1/2}+(1-x)^{1/2}$?

Awarded Apr 12 at 2:10

Schröchin

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How is Lebesgue integration "partitioning the range"?

Awarded Apr 11 at 15:57

user56834

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What is the most efficient way to find the area of a circle given three points on the rim

Awarded Apr 11 at 11:31

havakok

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Prove $\det(kA)=k^n\det A$ [closed]

Awarded Apr 11 at 8:11

user2185071

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Sum: $\sum_{n=1}^\infty\prod_{k=1}^n\frac{k}{k+a}=\frac{1}{a-1}$

Awarded Apr 11 at 7:40

Peter Woolfitt

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Lyapunov Theorem for beginners

Awarded Apr 11 at 7:26

Erel Segal-Halevi

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Fundamental theorem of calculus for complex analysis, proof

Awarded Apr 11 at 6:18

Vien Nguyen

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Find all entire functions that satisfy the following equality

Awarded Apr 11 at 1:57

Confused Integrator

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The Coordinate Ring: Its Etymology

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StormyTeacup

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What are some useful problem solving strategies for real analysis?

Awarded Apr 11 at 0:51

FNH

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Balanced but not convex?

Awarded Apr 10 at 12:35

Hui Yu

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Applications of Linear Programming to pure mathematics

Awarded Apr 10 at 9:03

Carla_

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Why are angles in "degrees" dimensionless?

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seeker

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Darth Vader Rule: what is the reason for its name, and a formal proof?

Awarded Apr 9 at 21:45

hyg17

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What is the "higher cohomology" version of the Eudoxus reals?

Awarded Apr 9 at 21:08

user263190

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Exotic Manifolds from the inside

Awarded Apr 9 at 16:34

Willem Noorduin

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Find the area of the region enclosed by $\frac{\sin x}{\sin y}=\frac{\sin x+\sin y}{\sin(x+y)}$ and the $x$-axis.

Awarded Apr 9 at 12:50

Dan

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Non-negative concave functions are non-decreasing

Awarded Apr 9 at 12:18

Andy

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Prove that every convex region is simply connected

Awarded Apr 9 at 12:18

Breton

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Slick proof that Coxeter groups $H_3$ and $H_4$ are finite?

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David E Speyer

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A formula for n-derivative of the inverse of a function?

Awarded Apr 8 at 16:41

Amir Kazemi

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Does every finite nilpotent group occur as a Frattini subgroup?

Awarded Apr 8 at 16:11

James

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Wavelet transform vs Windowed Fourier

Awarded Apr 8 at 14:47

Roman

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Is $ SU_2 \otimes SU_2 $ conjugate to $ SO_4(\mathbb{R}) $ in $ SU_4 $?

Awarded Apr 8 at 13:33

Ian Gershon Teixeira

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Is it possible to realize the Klein bottle as a linear group orbit?

Awarded Apr 8 at 13:33

Ian Gershon Teixeira

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Draw tangents at 3 random points on a circle to form a triangle. Show that the probability that a random side is shorter than the diameter is $1/2$.

Awarded Apr 8 at 11:35

Dan

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Endomorphism vector bundle isomorphic to the adjoint bundle of its frame bundle?

Awarded Apr 8 at 11:26

PhysicsMath

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Approximation of a harmonic function on the unit disc by harmonic polynomials.

Awarded Apr 8 at 7:16

JZS

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