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3 votes
2 answers
29 views

Hypocycloid problem. Show that the portion of every tangent line in the first quadrant is equal 1.

0 votes
0 answers
6 views

Deviation matrix of mixed number data sets

2 votes
1 answer
110 views
+50

Prove or disprove: $t \mapsto \mathbb{P}( X_t \in A)$ is measurable

0 votes
0 answers
38 views

Evaluate $\int_0^{\infty}\frac{\log( x)}{x^2+a^2} \,dx$ using contour integration; Re a > 0

0 votes
0 answers
12 views

Calculate a non trivial divider of a number

4 votes
1 answer
1k views

Bound on operator norm of block matrices

1 vote
0 answers
24 views

Does this implies $\mathcal{M}[T]_{\beta_1 \beta_2}$ is similar to the $\mathcal{M}[T]_{\beta_3 \beta_4}$?

1 vote
1 answer
29 views

Prove that even doubly periodic function satisfies a differential equation

0 votes
0 answers
9 views

Regarding a proof that $T(M\times N) \cong TM\times TN$

0 votes
0 answers
15 views

Contour integration of $\int_{0}^{+\infty}\frac{x^2\cos x}{\cosh x} \,{\rm d}x$

1 vote
1 answer
21 views

How to prove this property of conditional expectation $E(X f(Y) )=E(E(X|Y)f(Y))$

1 vote
1 answer
17 views

existence of non-zero proper T-invariant subspace

2 votes
1 answer
83 views

Prove that $\sum_{n=0}^\infty \frac{1}{(2n+1)^2}=\frac{\pi^2}{8}$

1 vote
2 answers
44 views

How to obtain heypercomplex numbers by an operation over complex numbers?

0 votes
1 answer
18 views

Limit of 2 variables: two similar cases with different outcomes

0 votes
0 answers
8 views

Approximation of PDF with summation to infinity, cos(x) and exp(x)

1 vote
1 answer
8 views

Understanding a step in a solution that limits in a metric space are unique

0 votes
0 answers
4 views

On the Sequence of Transformations of a Function

1 vote
0 answers
17 views

If $\sum_{cyc}\frac{a}{a+1}=1$ Show that $abc\le \frac{1}{8}$

1 vote
0 answers
17 views

How many unique permutations exist on this type of rubik's cube?

0 votes
0 answers
15 views

Expansion of determinants.

1 vote
0 answers
58 views

About three consecutive powerful integers

0 votes
0 answers
8 views

Unit speed torsion and curvature question

3 votes
3 answers
51 views

Proving that $\int^2_0fdx\ge1$ for a convex function

1 vote
0 answers
33 views

Evaluate $\sum_{n=1}^\infty (\frac{1}{2}\sin x)^n $

1 vote
1 answer
36 views

how can I linearize a constraint of the form sum(min(x(i),y(i))) for a linear optimisation problem?

0 votes
1 answer
24 views

Possibility of constructing an orthogonal matrix

1 vote
0 answers
14 views

Upper Bounds for Operator Norm of Block Diagonal matrix

-1 votes
0 answers
16 views

Does a 3x2 matrix have an identity? If yes, what is it?

0 votes
0 answers
23 views

Limit problem: How do I approach $\displaystyle \lim _{n\rightarrow \infty }\frac{\pi }{2^n}\sum _{j=1}^{2^n}\sin\left(\frac{j^{\pi }}{2^n}\right)$?

0 votes
0 answers
8 views

transcendental dimension of a variety

0 votes
0 answers
18 views

Looking for a cuvature tensor that adds up linearly

0 votes
0 answers
19 views

Find a limit of a series

0 votes
0 answers
19 views

Criterion for uniform continuity multivariable calculus

0 votes
0 answers
18 views
+50

Convergence of sum of MLE's over all possible $0/1$ sequences

0 votes
0 answers
5 views

Expectation using samples from a population

1 vote
1 answer
62 views

Which one should I start studying - Lie Groups/Algebras or Functional Analysis?

-3 votes
0 answers
14 views

You will get an A in this class if and only if you either do every exercise in this book or you get an A on the final?

0 votes
1 answer
19 views

Prove that $Z(A)= \cup_{i=1}^n p_i$

0 votes
1 answer
33 views

Find volume of solid bounded by $x^2+y^2=R^2,x^2+z^2=R^2$

0 votes
0 answers
22 views

Recovering a group from its irreducible representations?

0 votes
1 answer
18 views

For two objects X and Y in a category, with Y dominating X, prove that X dominates a Zero Object in our category.

0 votes
0 answers
6 views

Is johnson-lindenstrauss lemma valid for a set of high dimensional complex vectors?

2 votes
1 answer
3k views

Total number of paths between any two nodes - Graph vs. Complete Binary Tree

0 votes
0 answers
28 views

$n=s^2-t^2$ how many values can $s$ take?

-1 votes
0 answers
14 views

Let $n$ be an even number. How many $n$ fair coin flip sequences have the number of heads greater than or equal to the number of tails.

3 votes
2 answers
23 views

Must a certain continuous map have 0 in its image, given that its restriction to the unit sphere is homotopic to the identity?

0 votes
0 answers
10 views

Halting problem reduction, what am i doing wrong

0 votes
0 answers
30 views
+100

Sampling distribution of GBM Maximum-Likelihood estimator

3 votes
1 answer
15 views

Is it possible that liner tranform changes interval data to ratio?

1 vote
0 answers
13 views

A CSP on bit vector operations

4 votes
1 answer
49 views

What do the elements of the chains of a simplicial complex represent?

3 votes
0 answers
1k views

$\int\frac{\sqrt{9x^2-25}}{x}dx$. Using Trigonometric substitution, how to solve an integral when leading coefficient under radical isn't Unity?

0 votes
0 answers
9 views

Unbiased estimator of sample variance

0 votes
0 answers
11 views

Weak convergence and duals for $L_p$ involving time and probability space

1 vote
0 answers
6 views

Question on boundary of convex sets

1 vote
0 answers
15 views

Why do Mahlo cardinals imply the totality of the finite promise games

1 vote
1 answer
16 views

Positive column in the character table of finite groups

1 vote
0 answers
44 views

$2ix^4 − 10x^3 + (4 − 2i)x + 8 + 6i$ irreducible in $\mathbb Z[i][x]$ and in $\mathbb Q[i][x]$

3 votes
0 answers
52 views

An interesting recurrent equality, possibly easier to solve in its differential form?

-2 votes
0 answers
16 views

Two transitive groups with non-trivial normalizer

-1 votes
0 answers
8 views

Construct all non-trivial G-invariant partitions of the natural G-set X of the transitive permutation group G - Theoretical Complexity

1 vote
1 answer
18 views

How to find slant asymptote with exponential variable

0 votes
0 answers
4 views

Mapping an arbitrary 4 node quadrilateral element in space (x,y,z) to unit square

0 votes
1 answer
13 views

Proof of convergence of random variables in $L^p$ via convergence in probability and uniform integrability.

-1 votes
0 answers
28 views

In $L^1[0;1]$:Is every function bounded function defines only on irrational number only can be approximated by a continuous function?

0 votes
0 answers
5 views

Bound for $L^p$ Norm of a partial sum of a stationary sequence

0 votes
0 answers
10 views

How to construct a function to find the first member of an ordered pair given the pair's *n*-th position in a zig-zag enumeration

0 votes
0 answers
16 views

Is the closure of a positive convex cone positive?

0 votes
1 answer
19 views

Canonical morphism $\text{im}(f)\to\text{ker}(g)$ for exact sequence in an abelian category

1 vote
5 answers
77k views

Find the common ratio of the geometric series with the sum and the first term

0 votes
0 answers
18 views

what are the steps to get these value integration these functions?

2 votes
0 answers
18 views

Expressing the fundamental group of the Klein bottle as an HNN extension appears to contradict Britton's Lemma

2 votes
0 answers
14 views

If two functions are close apart can I prove the difference of their empirical loss is also small?

1 vote
0 answers
35 views

Let $f \in C^1(\mathbb{R})$ be such that both $f$ and $f'$ belong to $L^2(\mathbb{R})$. Show that $\hat{f} \in L^1(\mathbb{R})$

0 votes
0 answers
14 views

Integral of function with any test function along curve vanishes. Does that imply that the function must vanish?

0 votes
0 answers
26 views

Prob. $14$, Sec. $30$, in Munkres' TOPOLOGY, $2^{nd}$ ed: The product of a Lindelof space and a compact space is a Lindelof space

0 votes
0 answers
13 views

Hamiltonian paths in a 3 by n grid

1 vote
0 answers
27 views

Basic Geometry, extract relation between sides and angles

0 votes
0 answers
12 views

Relations properties, powerset

2 votes
0 answers
37 views

How to find the average distance between two points in a square of length $1$ by using Average = sum of all distances / number of pair of points?

1 vote
0 answers
22 views

Pell-Type Equation: show that the solutions $x,y$ are such that $\frac{x}{y}$ is a convergent

1 vote
0 answers
25 views

Calculate daily Sales budget from a monthly number based on daily sales Percentage.

1 vote
0 answers
8 views

definition of lie bracket of linear connection and a $\operatorname{End}(E)$-valued $k$-form

3 votes
0 answers
48 views

Prove that $\int_{0}^{1} x K(x) E(x) \,\mathrm{d} x{=}\frac{9}{16}+\frac{21}{32} \zeta(3)$

0 votes
0 answers
13 views

derivative of determinant, solve singularity equation for a variable

0 votes
0 answers
10 views

Inverting Fourier Transform for Heat Kernel

30 votes
0 answers
841 views

Can you make the triviality of $\langle a,b,c \mid aba^{-1} = b^2, bcb^{-1} = c^2, cac^{-1} = a^2 \rangle$ more trivial?

0 votes
0 answers
10 views

Absolute extrema of function vs. absolute extrema on closed interval of that function

0 votes
0 answers
9 views

How differentiate signals

0 votes
0 answers
30 views

Cardinal of a set challenge

1 vote
0 answers
15 views

intuition behind the construction of the map for showing associativity of $\pi_1(X,x_0)$.

0 votes
1 answer
26 views

Convergence of series over a complex lattice

1 vote
0 answers
5 views

How to the estimate as application of Strichartz Estimates?

0 votes
0 answers
19 views

If $X$ and $Y$ are conditionally independent given $Z$, and $X$ and $Z$ are conditionally independent given $Y$, are $X,Y,Z$ independent?

1 vote
1 answer
57 views

Is this a misprint or not?

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