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2 votes
0 answers
27 views

What is the maximum area of this structure made out of triangles?

0 votes
3 answers
37 views

Showing that $\lim_{z\to0}z\,\frac{\cos(z/2)}{\sin(z/2)}=2$

0 votes
0 answers
3 views

Solving Non-linear ode with elliptic integrals

0 votes
0 answers
9 views

Deficiency(?) in common set-theoretic development of natural numbers

1 vote
1 answer
11 views

Number of expected state transitions for two heads in a row with a fake coin?

0 votes
0 answers
12 views

Correlation, Orthogonality, and Independence of pair of random variables in a Venn diagram

2 votes
1 answer
30 views

Expected Value and Variance of Groups with All Women

0 votes
0 answers
9 views

Show there either a one-to-one function from $X$ into $Y$ or an onto function from $X$ onto $Y$ given a partially ordered set

0 votes
0 answers
18 views

Solving a system with more unknows than equations

0 votes
0 answers
5 views

A question on Ray class groups and the relative degree of a prime

4 votes
3 answers
87 views

How to get angles of a triangle given three slopes from each line

2 votes
1 answer
80 views

Prove $1 > 0$ in ordered field

1 vote
0 answers
29 views

Number of nodes in a game tree for a binary choice card game

1 vote
2 answers
974 views

Express the logarithm of number 63 to the base 140 in terms of a,b and c

2 votes
0 answers
11 views

Why is two variables enough to parametrize a surface?

0 votes
0 answers
10 views

Finding the number of factors

1 vote
0 answers
11 views

Every derivative function has a point of continuity.

0 votes
0 answers
18 views

Given a tangent line in point-slope form: $y = f'(4)(x-4) + y$, show what curves could be $f(x)$

0 votes
1 answer
1k views

How do you calculate the probability of an observation falling within a certain percentile?

3 votes
1 answer
109 views

Application of nonfamous finite groups in computer science

0 votes
1 answer
19 views

Why is the square of the first moment is always less than the second moment?

0 votes
0 answers
26 views

Does this integral converge and can it be solved or approximated analytically?

3 votes
1 answer
36 views
+50

Is the minimum length cycle basis necessarily made up of induced cycles?

2 votes
0 answers
18 views

Probability of winning with $\{1,\dots,9\}$ vs $\{1,\dots,8\}$

1 vote
0 answers
8 views

Existence of a subsequence that converges to a function weakly in $W^{2,p}$ and strongly in $L^p$

1 vote
1 answer
32 views

Number of unit preserving ring homomorphism

1 vote
0 answers
5 views

How to calculate the appreciation rate of a currency against itself?

1 vote
0 answers
25 views

Question on Pontryagin Duality

1 vote
0 answers
28 views

Given $p(x)=x^2+ax+b$, where $a,b\in \mathbb{Z}$. If $p(2020 + p(2020))=1$, find $a,b$

-1 votes
0 answers
4 views

Pooled estimators of two random variables - expectation and variance

1 vote
1 answer
65 views
+100

Proof-verification request: On the equation $\gcd(n^2,\sigma(n^2)) = D(n^2)/s(q^k)$ - Part II

-1 votes
0 answers
8 views

a random sample from a population with the following probability density function as n the picture and need to suse MoM and show, find var, estimator

2 votes
1 answer
26 views

Asymptotic distribution of $T= \frac{\hat{p_2}-\hat{p_1}}{\sqrt{\frac{2 \hat{p} \hat{q}}{n}}}$

1 vote
1 answer
26 views

How do I get an explicit formula for a geometric sequence with an additional term?

1 vote
1 answer
18 views

Find the largest possible area of $\triangle ABC. A(6,0), B(0,8)), C(x,y)$ where $x^2-16x+y^2-12y+91=0$

0 votes
0 answers
13 views

If $f_n \to f$ $\mu$-a.e. and $\|f_n\|_1 \to \|f\|$, then $\|f_n - f\| \to 0$

2 votes
0 answers
36 views

If $f(1)=c$ and $f(x+1) = f(x) + f(1)$, then is $f(x + y) = f(x) + f(y)$?

4 votes
3 answers
2k views

How can we derive the Interpolation formula for higher order?

1 vote
1 answer
42 views

Dot product between a vector and a matrix

0 votes
1 answer
28 views

Finding the range of $|\sin (x)|+|\cos (x)|$ by considering each quadrant as a separate case

4 votes
1 answer
27 views

Abscissa of convergence of a Dirichlet series with bounded coefficients and analytic continuation

4 votes
1 answer
133 views

How to prove Gauss's identities on the action of the operator $f' = x\frac{df}{dx}$ on Jacobi theta functions?

1 vote
1 answer
21 views

Interchanging random variables with the same distribution

2 votes
0 answers
36 views

Is there a combinatorial interpretation for a sum that includes $(-1)^k$?

0 votes
1 answer
33 views
+50

In a card game, what's the probability of a particular honour being with a particular split?

1 vote
0 answers
26 views

drawing backward bifurcation

1 vote
0 answers
7 views

Existence of a sequence that converges uniformly on compact subsets of the unit disk to a holomorphic function

2 votes
2 answers
27 views

How do I transform the following set of conditions into inequalities?

2 votes
1 answer
38 views

Help with a limit of a certain differential equation.

2 votes
1 answer
36 views

Doubt in Chapter 1 - Topology: A Categorical Approach

0 votes
0 answers
14 views

longest cycle in bipartite graph

0 votes
1 answer
18 views

solving biquadratic equations by ferrari method

6 votes
1 answer
421 views

How can I experiment with Lagrange multiplier in QCQP?

2 votes
1 answer
1k views

Determine Euler Angles from look, up, and cross vectors

3 votes
2 answers
27 views

Homogeneity on Minkowski functional

1 vote
0 answers
15 views

Induction as a theorem within the metatheory?

0 votes
0 answers
28 views

Bounding a $\ln(x)/\ln(y)$ expression where L'Hopital's rule doesn't help

1 vote
2 answers
26 views

Where does this order parameter come from?

0 votes
0 answers
17 views

Spivak: Proof that if $R$ is $(n+1)$-times diff. on $[a,b]$ and $R^{(k)}(a)=0$ then $\frac{R(x)}{(x-a)^{n+1}}=\frac{R^{(n+1)}(t)}{(n+1)!}$.

0 votes
1 answer
28 views

Is there an error in Wildberger's Line through two points theorem?

-3 votes
0 answers
16 views

Can the sign of a certain expression be deduced from another one?

5 votes
1 answer
47 views

Proving that every Cauchy sequence is bounded.

2 votes
2 answers
40 views

Solution verification: Show that $a_1 <_{(-1,1)} a_2\implies f(a_1)<_{\mathbb{R}} < f(a_2)$ to prove $(-1,1)$ has the same order type as $\mathbb{R}$

3 votes
0 answers
17 views

Does the Barr-embedding preserve coequalizers

1 vote
0 answers
32 views

Show that a vector field with curl = 0 contains no limit cycles

3 votes
1 answer
504 views

Number of unique cycle paths on an octahedron

1 vote
0 answers
40 views

Projective object in an abelian category: how can I form a direct sum?

15 votes
1 answer
608 views

Independence results that cannot be established by forcing.

1 vote
0 answers
49 views

Local coordinates identities

3 votes
1 answer
27 views

Understaning a field extension diagram

2 votes
1 answer
22 views

Solution Verification: An equivalence relation on finite subsets of $\mathbb{N}$, defined by having equal sums of the elements in the sets

0 votes
1 answer
31 views

Doubt formalizing one-step extensions of ZFC:

1 vote
0 answers
20 views

Can we always define principal ideal $(a)$ and divide original ring?

1 vote
0 answers
13 views

Can a differential equation be applied to aperiodic data?

1 vote
0 answers
49 views

L'Hôpital's rule proof in Spivak Calculus

0 votes
0 answers
16 views

Circulant-like determinant

2 votes
0 answers
15 views

Point-set topology in Theorem 6.15 of Le Gall: Brownian Motion, Martingales, and Stochastic Calculus

2 votes
4 answers
253 views

Is there a closed form solution to $e^{-x/b}(a+x) = e^{x/b}(a-x)$?

1 vote
1 answer
23 views

Showing that the image of a circle is a line that passes through the origin

0 votes
0 answers
14 views

Integral form of the Poisson equation

0 votes
0 answers
15 views

Limit Point of a Subset using Open Ball

0 votes
1 answer
13 views

Range of function using fundamental period

2 votes
1 answer
79 views

Wilson's proof of Iwasawa's Lemma

1 vote
2 answers
258 views

How to solve $x e^x + x = 1$?

0 votes
0 answers
9 views

Linear Regresssion: Multiple variables or build multiple models?

0 votes
0 answers
10 views

Two Binomial Distributions with conditional probability

1 vote
0 answers
24 views

Determinant of matrix with peculiar pattern

1 vote
0 answers
22 views

Number of permutations with condition on cumulative sum

2 votes
1 answer
75 views

Collinearity of the three roots of a cubic equation in the complex plane

1 vote
0 answers
6 views

Minimal spanning tree: Dual Formulation giving rise to nestedness property

3 votes
1 answer
204 views

Does Ramsey theory prove that all sufficiently long random sequences can be slightly compressed?

2 votes
1 answer
29 views

For $r\to 0$ $[\log(\log(r^2+1))-\log(\log(2))]^2r=[2\log(r)+o(\log(r))]^2r$?

-1 votes
2 answers
41 views

Finding all simple $R$ modules of a ring

11 votes
1 answer
145 views

Prove if $\sqrt{x+1}+\sqrt{y+2}+\sqrt{z+3}=\sqrt{y+1}+\sqrt{z+2}+\sqrt{x+3}=\sqrt{z+1}+\sqrt{x+2}+\sqrt{y+3}$, then $x=y=z$.

4 votes
3 answers
122 views

Parity Pattern of Triangle Numbers

4 votes
0 answers
28 views

Smoothing issues in integral inequality

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