Question: Let $k$ be a natural number . Then $3k+1$ , $4k+1$ and $6k+1$ cannot all be square numbers.


Question: Unexpected approximations which have led to important mathematical discoveries


Question: On Ramanujans curious equality for $\sqrt{2\,(1-3^{-2})(1-7^{-2})(1-11^{-2})\cdots} $


Question: Is $\lfloor n!/e\rfloor$ always even for $n\in\mathbb N$?


Question: How do I prove that a function is well defined?


Question: Is the rank of a matrix the same of its transpose? If yes, how can I prove it?


Question: Evaluating the indefinite integral $ \int \sqrt{\tan x} ~ \mathrm{d}{x}. $


Question: Proof that the irrational numbers are uncountable


Question: Can a complex number ever be considered bigger or smaller than a real number, or vice versa?


Question: Prove every odd integer is the difference of two squares


Question: how to be good at proving?


Question: Are there any examples of non-computable real numbers?


Question: What is a good book to study linear algebra?


Question: Why is empty set an open set?


Question: How to prove and interpret $\operatorname{rank}(AB) \leq \operatorname{min}(\operatorname{rank}(A), \operatorname{rank}(B))$?


Question: Probability for the length of the longest run in $n$ Bernoulli trials


Question: Proof of $(\mathbb{Z}/m\mathbb{Z}) \otimes_\mathbb{Z} (\mathbb{Z} / n \mathbb{Z}) \cong \mathbb{Z}/ \gcd(m,n)\mathbb{Z}$


Question: What do prime ideals in $k[x,y]$ look like?


Question: Characterizing units in polynomial rings


Question: Entire one-to-one functions are linear


Question: Let $X$ be an infinite dimensional Banach space. Prove that every Hamel basis of X is uncountable.


Question: How do you show monotonicity of the $\ell^p$ norms?


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


Question: How would you explain to a 9th grader the negative exponent rule?


Question: Why learn to solve differential equations when computers can do it?


Question: Big List of Fun Math Books


Question: What is the definition of a set?


Question: Is there such a thing as proof by example (not counter example)


Question: Can there be two distinct, continuous functions that are equal at all rationals?


Question: Whats the goal of mathematics?


Question: How to debug math?


Question: What does communicated by mean in math papers?


Question: Using Gröbner bases for solving polynomial equations


Question: Which is larger? $20!$ or $2^{40}$?


Question: Unsolved Problems due to Lack of Computational Power


Question: Whats wrong with this reasoning that $\frac{\infty}{\infty}=0$?


Question: Are there theoretical applications of trigonometry?


Question: The last digit of $2^{2006}$


Question: Intuition for the Importance of Modular Forms


Question: Linear Algebra Versus Functional Analysis


Question: Whats the point of studying topological (as opposed to smooth, PL, or PDiff) manifolds?


Question: Find three non-constant, pairwise unequal functions $f,g,h:\mathbb R\to \mathbb R$...


Question: Surprisingly elementary and direct proofs


Question: Closed Form for $~\int_0^1\frac{\text{arctanh }x}{\tan\left(\frac\pi2~x\right)}~dx$


Question: Is $n \sin n$ dense on the real line?


Question: When are nonintersecting finite degree field extensions linearly disjoint?


Question: The relation between trace and determinant of a matrix


Question: How to prove every closed interval in R is compact?


Question: Is there a step by step checklist to check if a multivariable limit exists and find its value?


Question: Is an automorphism of the field of real numbers the identity map?


Question: What do eigenvalues have to do with pictures?


Question: Why cant you flatten a sphere?


Question: List of problem books in undergraduate and graduate mathematics


Question: What is the importance of Calculus in todays Mathematics?


Question: Why does $\frac{1}{x} < 4$ have two answers?


Question: Explain this mathematical meme (Geometers bird interrupting Topologists bird)


Question: Coin flipping probability game ; 7 flips vs 8 flips


Question: Finite Groups with exactly $n$ conjugacy classes $(n=2,3,...)$


Question: Help understanding Algebraic Geometry


Question: 7 fishermen caught exactly 100 fish and no two had caught the same number of fish. Then there are three who have together captured at least 50 fish.


Question: Can a number have infinitely many digits before the decimal point?


Question: How can I show that $\sqrt{1+\sqrt{2+\sqrt{3+\sqrt\ldots}}}$ exists?


Question: Whats the intuition with partitions of unity?


Question: Center-commutator duality


Question: In how many different ways can a 9-panel comic grid be used?


Question: I need mathematical proof that the distance from zero to 1 is the equal to the distance from 1 to 2


Question: I almost quit self-studying mathematics, but should I continue?


Question: What is Trinity Hall Prime number?


Question: Examples of morphisms of schemes to keep in mind?


Question: Review of my T-shirt design


Question: Determinant of a rank $1$ update of a scalar matrix, or characteristic polynomial of a rank $1$ matrix


Question: Is A New Kind of Science a new kind of science?


Question: What am I doing when I separate the variables of a differential equation?


Question: Does every set have a group structure?


Question: Why do we use trig functions in Fourier transforms, and not other periodic functions?


Question: How to evaluate $I=\int_0^{\pi/2}x^2\ln(\sin x)\ln(\cos x)\ \mathrm dx$


Question: Is it possible to simplify $\frac{\Gamma\left(\frac{1}{10}\right)}{\Gamma\left(\frac{2}{15}\right)\ \Gamma\left(\frac{7}{15}\right)}$?


Question: Can squares of infinite area always cover a unit square?


Question: Whats the probability that a sequence of coin flips never has twice as many heads as tails?


Question: $5^n+n$ is never prime?


Question: What does it take to divide by $2$?


Question: If a two variable smooth function has two global minima, will it necessarily have a third critical point?


Question: Subgroups as isotropy subgroups and regular orbits on tuples


Question: A question about Sylow subgroups and $C_G(x)$


Question: How to know if a point is inside a circle?


Question: Poisson Distribution of sum of two random independent variables $X$, $Y$


Question: Explanation on arg min


Question: Product of two Gaussian PDFs is a Gaussian PDF, but Product of two Gaussian Variables is not Gaussian


Question: Is the product of symmetric positive semidefinite matrices positive definite?


Question: Matrices commute if and only if they share a common basis of eigenvectors?


Question: What are the formal names of operands and results for basic operations?


Question: Differentiating an Inner Product


Question: How to show that the commutator subgroup is a normal subgroup


Question: Nobody told me that self teaching could be so damaging...


Question: (undergraduate) Algebraic Geometry Textbook Recommendations


Question: Why is $\mathbb{Z}[\sqrt{-n}], n\ge 3$ not a UFD?


Question: Dot Product Intuition


Question: Divisor -- line bundle correspondence in algebraic geometry


Question: How to tell if Im good enough for graduate school?


Question: How is the derivative truly, literally the best linear approximation near a point?


Question: Why is the Continuum Hypothesis (not) true?


Question: Good examples of double induction


Question: A very general method for proving inequalities. Too good to be true?


Question: Is it possible to have three real numbers that have both their sum and product equal to $1$?


Question: What was the book that opened your mind to the beauty of mathematics?


Question: Research done by high-school students


Question: Why does the discriminant in the Quadratic Formula reveal the number of real solutions?


Question: Understanding the intuition behind math


Question: A circle rolls along a parabola


Question: Why is $\varphi$ called the most irrational number?


Question: How can I intuitively understand complex exponents?


Question: It looks straightforward, but actually it isnt


Question: Refuting the Anti-Cantor Cranks


Question: Could I be using proof by contradiction too much?


Question: Is there any geometric intuition for the factorials in Taylor expansions?


Question: Why do differential forms have a much richer structure than vector fields?


Question: A Challenging Logarithmic Integral $\int_0^1 \frac{\log(x)\log(1-x)\log^2(1+x)}{x}dx$


Question: Quadratic reciprocity via generalized Fibonacci numbers?


Question: Penroses remark on impossible figures


Question: Why are asymptotically one half of the integer compositions gap-free?


Question: Mirror algorithm for computing $\pi$ and $e$ - does it hint on some connection between them?


Question: Difference between ≈, ≃, and ≅


Question: What is the difference between only if and iff?


Question: Gradient of squared $2$-norm


Question: Distance/Similarity between two matrices


Question: Are all eigenvectors, of any matrix, always orthogonal?


Question: Area of a square inside a square created by connecting point-opposite midpoint


Question: How to generate random points on a sphere?


Question: Number of monic irreducible polynomials of prime degree $p$ over finite fields


Question: Should I be worried that I am doing well in analysis and not well in algebra?


Question: Negative versus Minus


Question: Discontinuous linear functional


Question: Geometric interpretation for sum of fourth powers


Question: The two-daughter-problem


Question: Has there ever been an application of dividing by $0$?


Question: Why do we miss 8 in the decimal expansion of 1/81, and 98 in the decimal expansion of 1/9801?


Question: Why does the Cauchy-Schwarz Inequality even have a name?


Question: What use is the Yoneda lemma?


Question: Is there a function whose antiderivative can be found but whose derivative cannot?


Question: Similar matrices and field extensions


Question: Are there mathematical concepts that exist in dimension $4$, but not in dimension $3$?


Question: Is there a definition of determinants that does not rely on how they are calculated?


Question: Unexpected use of topology in proofs


Question: Does this Fractal Have a Name?


Question: How is the Gödels Completeness Theorem not a tautology?


Question: How many 7-note musical scales are possible within the 12-note system?


Question: Approximating a $\sigma$-algebra by a generating algebra


Question: How do different definitions of degree coincide?


Question: What is the size of each side of the square?


Question: A non-losing strategy for tic-tac-toe $\times$ tic-tac-toe


Question: Can there be an injective function whose derivative is equivalent to its inverse function?


Question: Evaluating $\int_0^\infty \frac{dx}{\sqrt{x}[x^2+(1+2\sqrt{2})x+1][1-x+x^2-x^3+...+x^{50}]}$


Question: Trigonometric sums related to the Verlinde formula


Question: A bestiary about adjunctions


Question: Is OEIS A248049 an integer sequence?


Question: Prove that $\int_{0}^{1}\sin{(\pi x)}x^x(1-x)^{1-x}\,dx =\frac{\pi e}{24} $


Question: Golden Number Theory


Question: Explicit norm on $\mathcal{C}^0(\mathbb{R},\mathbb{R})$


Question: An illusionist and their assistant are about to perform the following magic trick


Question: The most effective windshield-wiper setup. (Packing a square with sectors)


Question: How prove this inequality $\sin{\sin{\sin{\sin{x}}}}\le\frac{4}{5}\cos{\cos{\cos{\cos{x}}}}$


Question: Period of the sum/product of two functions


Question: Example of Partial Order thats not a Total Order and why?


Question: What does curly (curved) less than sign $\succcurlyeq$ mean?


Question: Why we consider log likelihood instead of Likelihood in Gaussian Distribution


Question: Is there an equation to describe regular polygons?


Question: Eigenvalues of the rank one matrix $uv^T$


Question: Under what condition we can interchange order of a limit and a summation?


Question: Calculating pi manually


Question: Difference between basis and subbasis in a topology?


Question: Visualizing the 4th dimension.


Question: Why does the derivative of sine only work for radians?


Question: Origin of the dot and cross product?


Question: What is the arithmetic mean of no numbers?


Question: The $\sigma$-algebra of subsets of $X$ generated by a set $\mathcal{A}$ is the smallest sigma algebra including $\mathcal{A}$


Question: Would a proof to the Riemann Hypothesis affect security?


Question: What lies beyond the Sedenions


Question: Is it possible to determine if you were on a Möbius strip?


Question: Big O Notation is element of or is equal


Question: Is there a slowest rate of divergence of a series?


Question: Any smart ideas on finding the area of this shaded region?


Question: Can we calculate $ i\sqrt { i\sqrt { i\sqrt { \cdots } } }$?


Question: Is it possible that A counter-example exists but it cannot be found


Question: Applications of complex numbers to solve non-complex problems


Question: Is it an abuse of language to say *the* integers, *the* rational numbers, or *the* real numbers, etc.?


Question: Paradox: increasing sequence that goes to $0$?


Question: Is it possible to prove a mathematical statement by proving that a proof exists?


Question: Is $6.12345678910111213141516171819202122\ldots$ transcendental?


Question: Big list of guided discovery books


Question: Are there any Turing-undecidable problems whose undecidability is independent of the Halting problem?


Question: Funny double infinite sum


Question: Geometry problem involving infinite number of circles


Question: What proportion of positive integers have two factors that differ by 1?


Question: What are Different Approaches to Introduce the Elementary Functions?


Question: Finding triplets $(a,b,c)$ such that $\sqrt{abc}\in\mathbb N$ divides $(a-1)(b-1)(c-1)$


Question: How to think of the group ring as a Hopf algebra?


Question: Whats the value of this Viète-style product involving the golden ratio?


Question: Is $1+x+\frac{x^2}2+\dots+\frac{x^n}{n!}$ irreducible?


Question: How many values of $2^{2^{2^{.^{.^{.^{2}}}}}}$ depending on parenthesis?


Question: Looking for a definitive source about Dirichlet finally proving the Unit Theorem in the Sistine Chapel


Question: Whats the sign of $\det\left(\sqrt{i^2+j^2}\right)_{1\le i,j\le n}$?


Question: Is there a good reason why $\left\lfloor \frac{n!}{11e}\right\rfloor$ is always even?


Question: What does E mean in 9.0122222900391E-5?


Question: What’s the difference between analytical and numerical approaches to problems?


Question: How to find the multiplicity of eigenvalues?


Question: Is the power set of the natural numbers countable?


Question: Finding $\int x^xdx$


Question: Calculate on which side of a straight line is a given point located?


Question: Generating correlated random numbers: Why does Cholesky decomposition work?


Question: product distribution of two uniform distribution, what about 3 or more


Question: Dantzigs unsolved homework problems


Question: Interesting math-facts that are visually attractive


Question: How does TREE(3) grow to get so big? (Laymen explanation)


Question: Order of general- and special linear groups over finite fields.


Question: Why are two permutations conjugate iff they have the same cycle structure?


Question: What is an operator in mathematics?


Question: Does $ \int_0^{\infty}\frac{\sin x}{x}dx $ have an improper Riemann integral or a Lebesgue integral?


Question: Are there any differences between tensors and multidimensional arrays?


Question: Is it possible to write a sum as an integral to solve it?


Question: Why divide by $2m$


Question: Can math be subjective?


Question: Is there an easy way to see associativity or non-associativity from an operations table?


Question: Matrix is conjugate to its own transpose


Question: Is there a third dimension of numbers?


Question: Proving that $m+n\sqrt{2}$ is dense in $\mathbb R$


Question: What is the antiderivative of $e^{-x^2}$


Question: Is there a math expression equivalent to the conditional ternary operator?


Question: Understanding Gödels Incompleteness Theorem


Question: Do harmonic numbers have a “closed-form” expression?


Question: Is $\{0\}$ a field?


Question: How hard is the proof of $\pi$ or $e$ being transcendental?


Question: Interesting results easily achieved using complex numbers


Question: All natural numbers are equal.


Question: Geometrical interpretation of Ricci curvature


Question: Why are real numbers useful?


Question: $x^p-c$ has no root in a field $F$ if and only if $x^p-c$ is irreducible?


Question: What kind of work do modern day algebraists do?


Question: Choice of $q$ in Baby Rudins Example 1.1


Question: Why is there never a proof that extending the reals to the complex numbers will not cause contradictions?


Question: Is there any conjecture that we know is provable/disprovable but we havent found a proof of yet?


Question: Gaps or holes in rational number system


Question: What is $-i$ exactly?


Question: What knot is this?


Question: Doesnt the unprovability of the continuum hypothesis prove the continuum hypothesis?


Question: What is the fastest/most efficient algorithm for estimating Eulers Constant $\gamma$?


Question: What is the crime of lèse-Bourbaki?


Question: Natural example of cosets


Question: Is Complex Analysis equivalent Real Analysis with $f:\mathbb R^2 \to \mathbb R^2$?


Question: If $e^A$ and $e^B$ commute, do $A$ and $B$ commute?


Question: A discrete math riddle


Question: How does one give a mathematical talk?


Question: Probability that a quadratic equation has real roots


Question: How to identify surfaces of revolution


Question: Is there an abstract definition of a matrix being upper triangular?


Question: Self-learning mathematics - help needed!


Question: What is this pattern called?


Question: The $100$th derivative of $(x^2 + 1)/(x^3 - x)$


Question: Evaluate $\int_0^1\left(\frac{1}{\ln x} + \frac{1}{1-x}\right)^2 \mathrm dx$


Question: Infinite Series $\sum\limits_{n=1}^\infty\frac{(H_n)^2}{n^3}$


Question: In which ordered fields does absolute convergence imply convergence?


Question: Crazy pattern in the simple continued fraction for $\sum_{k=1}^\infty \frac{1}{(2^k)!}$


Question: A sequence that avoids both arithmetic and geometric progressions


Question: Proof of triangle inequality


Question: How to find the factorial of a fraction?


Question: What is the general equation of the ellipse that is not in the origin and rotated by an angle?


Question: Prove that the union of countably many countable sets is countable.


Question: Symbol for elementwise multiplication of vectors


Question: Difference between supremum and maximum


Question: What is difference between a ring and a field?


Question: Picking random points in the volume of sphere with uniform probability


Question: Necessity/Advantage of LU Decomposition over Gaussian Elimination


Question: Introductory Group theory textbook


Question: Does non-symmetric positive definite matrix have positive eigenvalues?


Question: Difference between Analytic and Holomorphic function


Question: Evaluating the nested radical $ \sqrt{1 + 2 \sqrt{1 + 3 \sqrt{1 + \cdots}}} $.


Question: Do matrices $ AB $ and $ BA $ have the same minimal and characteristic polynomials?


Question: What does it take to get a job at a top 50 math program in the U.S.?


Question: Is an irrational number odd or even?


Question: Definitions of Hessian in Riemannian Geometry


Question: How to calculate the pullback of a $k$-form explicitly


Question: How to prove that $\log(x)1$?


Question: Exam with $12$ yes/no questions (half yes, half no) and $8$ correct needed to pass, is it better to answer randomly or answer exactly 6 times yes?


Question: Distinguishing probability measure, function and distribution


Question: False proof: $\pi = 4$, but why?


Question: Books about the Riemann Hypothesis


Question: Why is $\text{Hom}(V,W)$ the same thing as $V^* \otimes W$?


Question: What is exactly the difference between a definition and an axiom?


Question: Non-associative operations


Question: Is $\sqrt{64}$ considered $8$? or is it $8,-8$?


Question: What is $\int_0^1\frac{x^7-1}{\log(x)}\mathrm dx$?


Question: Mathematical explanation behind a picture posted (lifted from facebook)


Question: Path-connected and locally connected space that is not locally path-connected


Question: Can I search for factors of $\ (11!)!+11!+1\ $ efficiently?


Question: Solutions to the matrix equation $\mathbf{AB-BA=I}$ over general fields


Question: Square root confusion: Why am I getting an answer if it doesnt work?


Question: Geometric understanding of differential forms.


Question: Why are the only division algebras over the real numbers the real numbers, the complex numbers, and the quaternions?


Question: What is the formula for pi used in the Python decimal library?


Question: Intuition for why the difference between $\frac{2x^2-x}{x^2-x+1}$ and $\frac{x-2}{x^2-x+1}$ is a constant?


Question: Axiom of choice and automorphisms of vector spaces


Question: Show that floating point $\sqrt{x \cdot x} \geq x$ for all long $x$.


Question: How to entertain a crowd with mathematics?


Question: Colliding Bullets


Question: False beliefs about Lebesgue measure on $\mathbb{R}$


Question: Evaluating $\int P(\sin x, \cos x) \text{d}x$


Question: Is there a geometric idea behind Sylows theorems?


Question: Is $29$ the only prime of the form $p^p+2$?


Question: Is Stokes Theorem natural in the sense of category theory?


Question: Trying to define $\mathbb{R}^{0.5}$ topologically


Question: Conjectured value of a harmonic sum $\sum_{n=1}^\infty\left(H_n-\,2H_{2n}+H_{4n}\right)^2$


Question: Elementary proof that the derivative of a real function is continuous somewhere


Question: Can $\sqrt{p}^{\sqrt{p}^{\sqrt{p}}}$ be an integer, if $p$ is a non-square positive integer?


Question: How to tell if a set of vectors spans a space?


Question: Easy way of memorizing values of sine, cosine, and tangent


Question: What does ∈ mean?


Question: Recognizable vs Decidable


Question: Why have we chosen our number system to be decimal (base 10)?


Question: How the product of two integrals is iterated integral? $\int\cdot \int = \iint$


Question: How to take the gradient of the quadratic form?


Question: Why cant a set have two elements of the same value?


Question: Order of finite fields is $p^n$


Question: Why is $A^TA$ invertible if $A$ has independent columns?


Question: Proof that the largest eigenvalue of a stochastic matrix is $1$


Question: how does expectation maximization work?


Question: Are functions of independent variables also independent?


Question: What is an intuitive explanation for $\operatorname{div} \operatorname{curl} F = 0$?


Question: What is the difference between projected gradient descent and ordinary gradient descent?


Question: Functions which are Continuous, but not Bicontinuous


Question: Choose a random number between $0$ and $1$ and record its value. Keep doing it until the sum of the numbers exceeds $1$. How many tries do we need?


Question: How I can prove that the sequence $\sqrt{2} , \sqrt{2\sqrt{2}}, \sqrt{2\sqrt{2\sqrt{2}}}$ converges to 2?


Question: Difference between bijection and isomorphism?


Question: $\lim\limits_{n \to{+}\infty}{\sqrt[n]{n!}}$ is infinite


Question: An easy example of a non-constructive proof without an obvious fix?


Question: Why doesnt induction extend to infinity? (re: Fourier series)


Question: A really complicated calculus book


Question: Why isnt several complex variables as fundamental as multivariable calculus?


Question: Parabola is an ellipse, but with one focal point at infinity


Question: Formal definition of conditional probability


Question: Why is it worth spending time on type theory?


Question: Why is cross product defined in the way that it is?


Question: What are the rules for equals signs with big-O and little-o?


Question: What book can bridge high school math and the more advanced topics?


Question: Foundation for analysis without axiom of choice?


Question: Intuition behind ideal


Question: How far is the list of known primes known to be complete?


Question: Why the real and imaginary parts of a complex analytic function are not independent?


Question: Do circles divide the plane into more regions than lines?


Question: On the functional square root of $x^2+1$


Question: $n!+1$ being a perfect square


Question: Does $\zeta(3)$ have a connection with $\pi$?


Question: Why do we need so many trigonometric definitions?


Question: Prove that the sum of pythagorean triples is always even


Question: What is the explanation for this visual proof of the sum of squares?


Question: Why are topological spaces interesting to study?


Question: Good math books to discover stuff by yourself


Question: Integral $\int_{-1}^{1} \frac{1}{x}\sqrt{\frac{1+x}{1-x}} \log \left( \frac{(r-1)x^{2} + sx + 1}{(r-1)x^{2} - sx + 1} \right) \, \mathrm dx$


Question: Why is it that $\mathbb{Q}$ cannot be homeomorphic to _any_ complete metric space?


Question: Why is the Laplacian important in Riemannian geometry?


Question: MIT 2015 Integration Question


Question: Is there a name for this type of polygon?


Question: Intuition behind Snake Lemma


Question: Is it possible for a function to be smooth everywhere, analytic nowhere, yet Taylor series at any point converges in a nonzero radius?


Question: Proof that a trigonometric function of a rational angle must be non-transcendental


Question: Does $|n^2 \cos n|$ diverge to $+\infty$?


Question: What are exact sequences, metaphysically speaking?


Question: What structure does the alternating group preserve?


Question: About the integral $\int_{0}^{+\infty}\sin(x\,\log x)\,dx$


Question: Effective Research Notes


Question: A new continued fraction for Apérys constant, $\zeta(3)$?


Question: Two questions about weakly convergent series related to $\sin(n^2)$ and Weyls inequality


Question: What is the integral of 1/x?


Question: How does one denote the set of all positive real numbers?


Question: Prove: If a sequence converges, then every subsequence converges to the same limit.


Question: How many prime numbers are known?


Question: What books are prerequisites for Spivaks Calculus?


Question: Create unique number from 2 numbers


Question: What is the main difference between a vector space and a field?


Question: If eigenvalues are positive, is the matrix positive definite?


Question: $\epsilon$-$\delta$ proof that $\lim\limits_{x \to 1} \frac{1}{x} = 1$.


Question: Finding Value of the Infinite Product $\prod \Bigl(1-\frac{1}{n^{2}}\Bigr)$


Question: Pen, pencils and paper to write math


Question: Video lectures on Real Analysis?


Question: If $a^3 =a$ for all $a$ in a ring $R$, then $R$ is commutative.


Question: Which of the numbers $1, 2^{1/2}, 3^{1/3}, 4^{1/4}, 5^{1/5}, 6^{1/6} , 7^{1/7}$ is largest, and how to find out without calculator?


Question: Zero divided by zero must be equal to zero


Question: Proof that every number ≥ $8$ can be represented by a sum of fives and threes.


Question: What is the difference between a Ring and an Algebra?


Question: Intuitive understanding of the derivatives of $\sin x$ and $\cos x$


Question: A linear operator commuting with all such operators is a scalar multiple of the identity.


Question: Prove that if $(ab)^i = a^ib^i \forall a,b\in G$ for three consecutive integers $i$ then G is abelian


Question: Is $\pi$ equal to $180^\circ$?


Question: Is every Lebesgue measurable function on $\mathbb{R}$ the pointwise limit of continuous functions?


Question: Seeking a laymans guide to Measure Theory


Question: What are the Laws of Rational Exponents?


Question: An intuitive approach to the Jordan Normal form


Question: Intuitive Understanding of the constant $e$


Question: How far can one see over the ocean?


Question: Every power series is the Taylor series of some $C^{\infty}$ function


Question: Is the axiom of choice really all that important?


Question: On average, how many friends would I need to have to have at least one friends birthday every day?


Question: Is there a purely algebraic proof of the Fundamental Theorem of Algebra?


Question: What books should I get to self study beyond Calculus for someone about to start undergrad mathematics?


Question: Are there any objects which arent sets?


Question: What is the theme of analysis?


Question: Is there any geometric way to characterize $e$?


Question: Why and How do certain manipulations in indefinite integrations just work?


Question: History of the Concept of a Ring


Question: Simplest way to get the lower bound $\pi > 3.14$


Question: What to answer when people ask what I do in mathematics


Question: How many super imaginary numbers are there?


Question: Fibonacci infinite sum resulting in $\pi$


Question: Is $i = \sqrt{e^{\pi\sqrt{e^{\pi\sqrt\ldots}}}}$?


Question: Example of a compact set that isnt the spectrum of an operator


Question: Why is one $\infty$ number enough for complex numbers?


Question: How do the Catalan numbers turn up here?


Question: What is so special about $\alpha=-1$ in the integral of $x^\alpha$?


Question: To evaluate $\int_0^{+\infty} \frac{\;\mathrm dx}{\sqrt[3]{x^3+a^3}\sqrt[3]{x^3+b^3}\sqrt[3]{x^3+c^3}}$


Question: On a long proof


Question: Why do all the Platonic Solids exist?


Question: Bijection $f\colon\mathbb{N}\to\mathbb{N}$ with $f(0)=0$ and $|f(n)-f(n-1)|=n$


Question: How to solve an nth degree polynomial equation


Question: Number of onto functions


Question: What does := mean?


Question: Adding two polar vectors


Question: Sum of the alternating harmonic series $\sum_{k=1}^{\infty}\frac{(-1)^{k+1}}{k} = \frac{1}{1} - \frac{1}{2} + \cdots $


Question: Average Distance Between Random Points on a Line Segment


Question: Understanding Dot and Cross Product


Question: What are good books/other readings for elementary set theory?


Question: Best Algebraic Topology book/Alternative to Allen Hatcher free book?


Question: What is the implicit function theorem?


Question: What does it mean to integrate with respect to the distribution function?


Question: Very good linear algebra book.


Question: Can a piece of A4 paper be folded so that its thick enough to reach the moon?


Question: Every nonzero element in a finite ring is either a unit or a zero divisor


Question: Projection is an open map


Question: Can someone explain Cayleys Theorem step by step?


Question: Lemma/Proposition/Theorem, which one should we pick?


Question: Game theory - self study


Question: What are the required backgrounds of Robin Hartshornes Algebraic Geometry book?


Question: Semi-direct v.s. Direct products


Question: Why is it that if I count years from 2011 to 2014 as intervals I get 3 years, but if I count each year separately I get 4 years?


Question: What exactly is infinity?


Question: How do we know the ratio between circumference and diameter is the same for all circles?


Question: Good introductory book on geometric algebra


Question: Jacobi identity - intuitive explanation


Question: Why does the volume of the unit sphere go to zero?


Question: Is it possible to place 26 points inside a rectangle that is 20 cm by 15 cm so that the distance between every pair of points is greater than 5 cm?


Question: What does it mean to solve an equation?


Question: Isomorphic quotients by isomorphic normal subgroups


Question: How can this function have two different antiderivatives?


Question: Why arent integration and differentiation inverses of each other?


Question: Is 128 the only multi-digit power of 2 such that each of its digits is also a power of 2?


Question: Do we really need reals?


Question: How can someone reject a math result if everything has to be proved?


Question: What are some things we can prove they must exist, but have no idea what they are?


Question: I dont understand Gödels incompleteness theorem anymore


Question: Where to begin with foundations of mathematics


Question: Development of the Idea of the Determinant


Question: Do we need to formally teach the Greek Alphabet?


Question: The Meaning of the Fundamental Theorem of Calculus


Question: A conjecture involving prime numbers and circles


Question: Is the percentage symbol a constant?


Question: Is a proof still valid if only the writer understands it?


Question: Set Theoretic Definition of Numbers


Question: Why cant Antoines necklace fall apart?


Question: Areas versus volumes of revolution: why does the area require approximation by a cone?


Question: Designing an Irrational Numbers Wall Clock


Question: Must eigenvalues be numbers?


Question: How does the divisibility graphs work?


Question: Axiom of Choice: Where does my argument for proving the axiom of choice fail? Help me understand why this is an axiom, and not a theorem.


Question: The identity cannot be a commutator in a Banach algebra?


Question: If the field of a vector space werent characteristic zero, then what would change in the theory?


Question: What are some math books written in dialogue or story form, e.g., a teacher explaining to a student?


Question: A zero sum subset of a sum-full set


Question: Why cant we define more elementary functions?


Question: A conjectured closed form of $\int\limits_0^\infty\frac{x-1}{\sqrt{2^x-1}\ \ln\left(2^x-1\right)}dx$


Question: Sheldon Cooper Primes


Question: Notations that are mnemonic outside of English


Question: Hidden patterns in $\sin(a x^2)$


Question: AM-GM-HM Triplets


Question: Why is the Galois Correspondence intuitively plausible?


Question: Generalizing the sum of consecutive cubes $\sum_{k=1}^n k^3 = \Big(\sum_{k=1}^n k\Big)^2$ to other odd powers


Question: A curious equality of integrals involving the prime counting function?


Question: Xmas Maths 2015


Question: How to evaluate $\int_0^\infty\operatorname{erfc}^n x\ \mathrm dx$?


Question: Time to reach a final state in a random dynamical system (answer known, proof unknown)


Question: What numbers can be created by $1-x^2$ and $x/2$?


Question: Is there a way to get trig functions without a calculator?


Question: Sample Standard Deviation vs. Population Standard Deviation


Question: Why does an integral change signs when flipping the boundaries?


Question: Why is the absolute value function not differentiable at $x=0$?


Question: Effect of elementary row operations on determinant?


Question: Do all square matrices have eigenvectors?


Question: Is zero a prime number?


Question: How to find a basis for the intersection of two vector spaces in $\mathbb{R}^n$?


Question: Subgroup of index $2$ is Normal


Question: The generating function for the Fibonacci numbers


Question: Examples of infinite groups such that all their respective elements are of finite order.


Question: Why are $3D$ transformation matrices $4 \times 4$ instead of $3 \times 3$?


Question: Show that $\langle 2,x \rangle$ is not a principal ideal in $\mathbb Z [x]$


Question: Every linear mapping on a finite dimensional space is continuous


Question: difference between maximal element and greatest element


Question: How can a set contain itself?


Question: Sum of two closed sets in $\mathbb R$ is closed?


Question: How unique are $U$ and $V$ in the Singular Value Decomposition?


Question: Are normal subgroups transitive?


Question: Why is the ring of matrices over a field simple?


Question: In set theory, how are real numbers represented as sets?


Question: Is it possible to plot a graph of any shape?


Question: Proving $\frac{\sin x}{x} =\left(1-\frac{x^2}{\pi^2}\right)\left(1-\frac{x^2}{2^2\pi^2}\right) \left(1-\frac{x^2}{3^2\pi^2}\right)\cdots$


Question: Subgroups of finitely generated groups are not necessarily finitely generated


Question: $|G|>2$ implies $G$ has non trivial automorphism


Question: There exists a power of 2 such that the last five digits are all 3s or 6s. Find the last 5 digits of this number


Question: Does a Fourier transformation on a (pseudo-)Riemannian manifold make sense?


Question: $\sin 1^\circ$ is irrational but how do I prove it in a slick way? And $\tan(1^\circ)$ is .....


Question: How many fair dice exist?


Question: How to start a math blog?


Question: Modus moron rule of inference?


Question: precise official definition of a cell complex and CW-complex


Question: Alternative proofs that $A_5$ is simple


Question: Can you give me some concrete examples of magmas?


Question: Does Monty Hall logic apply to this real world situation?


Question: Are there dictionaries in math?


Question: How did early mathematicians make it without Set theory?


Question: Sharing a pepperoni pizza with your worst enemy


Question: Is it wrong to tell children that $1/0 =$ NaN is incorrect, and should be $∞$?


Question: Why is the Daniell integral not so popular?


Question: Say $a=b$. Is Do the same thing to both sides of an equation, and it still holds an axiom?


Question: Why is there antagonism towards extended real numbers?


Question: What is a topological space good for?


Question: Are rational points dense on every circle in the coordinate plane?


Question: What do mathematicians mean by equipped?


Question: Category-theoretic limit related to topological limit?


Question: Notation for an interval when you dont know which bound is greater


Question: Why can we use induction when studying metamathematics?


Question: Finding the value of $\sqrt{1+2\sqrt{2+3\sqrt{3+4\sqrt{4+5\sqrt{5+\dots}}}}}$


Question: What if $\pi$ was an algebraic number? (significance of algebraic numbers)


Question: Solution to the equation of a polynomial raised to the power of a polynomial.


Question: Are commutative C*-algebras really dual to locally compact Hausdorff spaces?


Question: Is $dx\,dy$ really a multiplication of $dx$ and $dy$?


Question: Proving $\sum_{n=-\infty}^\infty e^{-\pi n^2} = \frac{\sqrt[4] \pi}{\Gamma\left(\frac 3 4\right)}$


Question: How do you prove Gautschis inequality for the gamma function?


Question: Function that is the sum of all of its derivatives


Question: Identity for simple 1D random walk


Question: Prove $\int\limits_{0}^{\pi/2}\frac{dx}{1+\sin^2{(\tan{x})}}=\frac{\pi}{2\sqrt{2}}\bigl(\frac{e^2+3-2\sqrt{2}}{e^2-3+2\sqrt{2}}\bigr)$


Question: How to maintain enthusiasm and joy in teaching when the material grows stale


Question: An exotic sequence


Question: Making trigonometric substitutions rigorous


Question: A new kind of fractal?


Question: How do you go about doing mathematics on a day to day basis?


Question: $C^{k}$-manifolds: how and why?


Question: Why do I only breathe out of one nostril?


Question: Why are so few foods blue?


Question: Does DNA have the equivalent of IF-statements, WHILE loops, or function calls? How about GOTO?


Question: How many times did terrestrial life emerge from the ocean?


Question: Do bacteria die of old age?


Question: Is there a reason why human eyesight and plants make use of the same wavelength of light?


Question: Why is thymine rather than uracil used in DNA?


Question: Are male and female brains physically different from birth?


Question: What is the effect of non-vaccinated people on vaccinated people?


Question: Why do plants have green leaves and not red?


Question: Can HIV be transmitted via mosquitos?


Question: Whats the evidence against SARS-CoV-2 being engineered by humans?


Question: Do beneficial viruses exist? If so, what examples are there?


Question: Does the string ...CATCAT... appear in the DNA of Felis catus?


Question: Why did the process of sleep evolve in many animals? What is its evolutionary advantage?


Question: Are humans the only species who drink milk as adults?


Question: How could humans have interbred with Neanderthals if were a different species?


Question: Why do some bad traits evolve, and good ones dont?


Question: Death because of distilled water consumption


Question: Why is the heart not in the middle of the body?


Question: Why 20 amino acids instead of 64?


Question: Is there an RGB equivalent for smells?


Question: Whats up with this leaf?


Question: How does the brains energy consumption depend on mental activity?


Question: Do animals exhibit handedness (paw-ness?) preference?


Question: Why do Humans not produce Vitamin C like other mammals?


Question: Why shouldnt dogs eat chocolate?


Question: Why are there no wheeled animals?


Question: What is the evolutionary advantage of red-green color blindness?


Question: Do ants or other insects sleep, and if so why?


Question: What could cause a forest of bent trees?


Question: Is there any evidence that sexual selection may lead to extinction of species?


Question: Why does evolution not make our life longer?


Question: Why does it hurt the next day after doing significant exercise?


Question: Can a woman give birth to twins with different fathers?


Question: Are there organisms with fewer than 1000 neurons?


Question: How come large herbivores have such thin legs?


Question: A new species of small bird?


Question: Why dont mammals have more than 4 limbs?


Question: Why do smaller mammals move intermittently?


Question: Are the social-distancing measures implemented against SARS-CoV-2 also suppressing the spread of other viruses?


Question: Why do the fastest runners tend to be black?


Question: Life without DNA?


Question: What is the benefit of fever during infections?


Question: Why isnt a virus alive?


Question: Why do men have nipples?


Question: Why are there no organisms with metal body parts, like weapons, bones, and armour? (Or are there?)


Question: Human perception of time depending on age


Question: Do large animals experience a meaningful delay when moving their most distant appendages?


Question: Why does cracking a joint make noise?