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Interesting log sine integrals $\int_0^{\pi/3} \log^2 \left(2\sin \frac{x}{2} \right)dx= \frac{7\pi^3}{108}$

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Random Variable

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Why does factoring eliminate a hole in the limit?

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Euro Micelli

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Why do we sometimes lose solutions when solving equations?

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Tanner Swett

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What situation calls for dividing the standard deviation by $\sqrt n$?

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Ritayan B

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How to prove that homomorphism from field to ring is injective or zero?

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Rudy the Reindeer

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What is the Fourier transform of $1/|x|$?

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Sangchul Lee

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Noetherian property for exact sequence

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Martin Brandenburg

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Find a simple proof that π is irrational

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Especially Lime

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Does one accepted false statement allow proving anything?

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MJD

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The closure of a connected set in a topological space is connected

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mss

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How do you prove that differentiability implies continuity with $\epsilon$-$\delta$ definition?

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Ayman Hourieh

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Why is every abelian group the direct limit of its finitely generated subgroups?

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Arturo Magidin

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Calculate residue at essential singularity

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Simon

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How to prove $\text{Rank}(AB)\leq \min(\text{Rank}(A), \text{Rank}(B))$?

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Dave Au

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Is the inverse of a linear transformation linear as well?

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Marc van Leeuwen

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An example showing that van der Waerden's theorem is not true for infinite arithmetic progressions

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Martin Sleziak

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Find a simple proof that π is irrational

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Jam

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Linear span of the empty set

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Denis

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Additive category that is not abelian

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Jeremy Rickard

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A good book for metric spaces?

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Pete L. Clark

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Reflection across a line?

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leonbloy

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Define a Principal Branch in Complex Analysis

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Ted

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How to obtain the Laurent expansion of gamma function around $z=0$?

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Mark Viola

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Fake induction proofs

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Andrew Woods

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Are all functions that have an inverse bijective functions?

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Patrick Da Silva

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In a finite field product of non-square elements is a square

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egreg

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Understanding the assumptions in the Reverse Fatou's Lemma

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Davide Giraudo

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Is there an idempotent element in a finite semigroup?

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hmakholm left over Monica

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Is it possible to "sort" a continuous function?

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Robert Israel

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Factorize the polynomial $x^3+y^3+z^3-3xyz$

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Elensil

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Recommendations for Numerical Analysis texts?

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Amzoti

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Isn't square root a bit like Log()?

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Anonymous

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Evaluating $\int_0^{\infty}\frac{\ln(x^2+1)}{x^2+1}dx$

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Ron Gordon

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How many faces does the resulting polyhedron have?

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Judith L

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Limit of $L^p$ norm when $p\to0$

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Davide Giraudo

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Is there a memorable solution to Kirkman's School Girl Problem?

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String

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How is GNFS the best factoring algorithm when its time complexity exceeds brute-force?

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HallaSurvivor

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Spin manifold and the second Stiefel-Whitney class

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Qiaochu Yuan

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What's wrong with this picture? Impossible circles.

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timon92

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Prove: The pre-image of an ideal is an ideal.

Awarded Nov 26 at 17:41

David P

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Show that $f(x)=1/ x$ is continuous at any $c\neq 0$

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copper.hat

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Wielandt's proof of Sylow's theorem.

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Derek Holt

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Two seemingly contradictory series in a calc 2 exam

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Gonçalo

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A question of random points in a square and probability of intersection of their line segments

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Empy2

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How to prove that minimum of two exponential random variables is another exponential random variable?

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Silverfish

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Outer Product of Two Matrices?

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davcha

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Lecture Notes for Hatcher's Algebraic Topology

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Alvin Jin

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On the sum of digits of $2^x$

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Ethan Bolker

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Cardinality of set of real continuous functions

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Dejan Govc

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Span of an empty set is the zero vector

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Qiaochu Yuan

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Strategies to denest nested radicals $\sqrt{a+b\sqrt{c}}$

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Michael Rozenberg

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Covectors and Vectors

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Aaron

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What is the parametric equation of a rotated Ellipse (given the angle of rotation)

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Gil Epshtain

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Linear independence of function vectors and Wronskians

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Bill Cook

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Distribution of the difference of two normal random variables.

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Jonathan H

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The word problem for finite groups

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Bill Dubuque

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Diagonalizable matrices with complex values are dense in set of $n\times n$ complex matrices.

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Pierre-Yves Gaillard

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An ideal that is maximal among non-finitely generated ideals is prime.

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DonAntonio

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Is enumerating squares via $(a+1)^2 = a^2+(2a+1)$ a new method to find square roots?

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MJD

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Generalized mean value theorem

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pitonist

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