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Excavator

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Awarded 10882 times.

If $\frak{g}$ is a real Lie algebra, why is the Killing form of its complexification the same?

Awarded Apr 1 at 4:17

user1589421

135 bronze badges

Proof on Fibonacci sequence: $F(1) + F(3) + \cdots + F(2n-1) = F(2n)$ using induction and recursion

Awarded Apr 1 at 4:17

Emeth

53 bronze badges

Radius vs Radius of curvature of an ellipse

Awarded Apr 1 at 4:17

Ilaggo

32 bronze badges

Is there any easy way to understand the definition of Gaussian Curvature?

Awarded Mar 31 at 17:52

ramslök USv

1651 silver badge7 bronze badges

Evaluating $\int_{\frac\pi 6}^{\frac \pi 3} \frac{\cos^2x}{x(\pi-x)}\mathrm dx$

Awarded Mar 30 at 22:11

Bachelor

1,0801 silver badge16 bronze badges

How to proof that $f^{-1}(\sigma(\mathcal C))\subseteq\sigma(f^{-1}(\mathcal C))$?

Awarded Mar 30 at 4:10

Chstellar

32 bronze badges

How do I calculate the double integral of a Hankel function?

Awarded Mar 30 at 4:10

Natural logarithm

32 bronze badges

Why aren't the values true and false part of logic, which is concerned only with the preservation of truth in arguments?

Awarded Mar 30 at 4:10

Otakar Molnár López

598 bronze badges

Help determining best strategy to play a game

Awarded Mar 28 at 4:09

Michael T

1,4291 silver badge22 bronze badges

Is there a name for the function $f(x)=\max(a, \min(x, b))$, where $a \leq b$?

Awarded Mar 28 at 4:09

FxMySz

477 bronze badges

On The Horizontal And Slanted Asymptotes Of Rational Functions

Awarded Mar 28 at 4:09

Percival the caterpillar

658 bronze badges

Is there a classification of regular maps $\mathbb{P}^1(k)\to\mathbb{A}^1(k)$?

Awarded Mar 27 at 6:11

geom123

234 bronze badges

Type Theory for Beginners

Awarded Mar 26 at 5:10

Daryl Chew

32 bronze badges

Convexity of Bregman divergence

Awarded Mar 26 at 5:10

Sillybear

455 bronze badges

integrals involving minimum function

Awarded Mar 26 at 5:10

Yilin Cheng

3651 silver badge8 bronze badges

Asymptotic rays in $\mathrm{CAT}(-1)$ spaces

Awarded Mar 25 at 4:40

S.T.

7395 silver badges17 bronze badges

How does remainder theorem work even though we are technically dividing by zero?

Awarded Mar 25 at 4:40

philipxy

1117 bronze badges

How to show that $\mathrm{Tor}_{2}^{\mathbb{Z}}=0$

Awarded Mar 24 at 4:07

shwsq

7361 silver badge16 bronze badges

Closure of the union = Union of closures

Awarded Mar 24 at 4:07

Nonlinear

1034 bronze badges

Maximal tamely ramified abelian extension of $\mathbb{Q}_p$ is finite over the maximal unramified extension $\mathbb{Q}_p^{nr}$?

Awarded Mar 23 at 4:04

Enguerrand Moulinier

77110 bronze badges

Relationship Between Free Group Actions of a Finite Set

Awarded Mar 23 at 4:04

Jon Merladet

134 bronze badges

Find a complete sufficient statistics, or show that one does not exist.

Awarded Mar 22 at 4:03

AVISHEK GHORAI

34 bronze badges

Difference between Bezier segment and B-spline

Awarded Mar 22 at 4:03

cubuspl42

1055 bronze badges

Problems that become easier in a more general form

Awarded Mar 21 at 6:26

ricma

1134 bronze badges

Can a point be reflected through a line which is not straight?

Awarded Mar 21 at 6:26

maximusavant25

398 bronze badges

In a ring (why) does $b=c\Rightarrow ab = ac$? [duplicate]

Awarded Mar 20 at 18:57

Brandon Harad

1881 silver badge11 bronze badges

Motivation and examples for ramification

Awarded Mar 20 at 4:20

AU2tT

155 bronze badges

Imaginary to the power of fractional number.

Awarded Mar 19 at 4:08

Garv Singhal

34 bronze badges

Integers $n$ for which $|2^n + 5^n – 65|$ is a perfect square

Awarded Mar 19 at 4:08

redoc

5412 bronze badges

difference between runge kutta methods of same order

Awarded Mar 18 at 4:27

Arbel Groshaus

1032 bronze badges

The integral of $e^{-x^2}$

Awarded Mar 18 at 4:27

CherryDT

1256 bronze badges

<p> is a prime ideal iff p is a prime (integral domain)

Awarded Mar 18 at 4:27

Seth

3,9811 gold badge16 silver badges26 bronze badges

Suppose $f\in H(U), f(U) \subseteq U$. How many zeros can $f$ have in the disc $D(0,\beta)$?

Awarded Mar 18 at 4:27

user1585259

32 bronze badges

$\int\frac{\sqrt{9x^2-25}}x\mathrm dx$: using trig substitution, how to evaluate such integrals when leading coefficient under radical isn't unity?

Awarded Mar 17 at 5:16

Poonguzhali Annadurai

91120 bronze badges

If $a$, $b$, $c$, $d$ are positive reals so $(a+c)(b+d) = 1$, prove the following inequality would be greater than or equal to $\frac {1}{3}$.

Awarded Mar 17 at 5:16

Yiyj1

397 bronze badges

Degree and basis of field extension $\mathbb{Q}[\sqrt{2+\sqrt{5}}]$

Awarded Mar 17 at 5:16

whoami730

636 bronze badges

How to prove $e^x\ge \left(1+\frac xn\right)^n$ for any real numbers $x, n > 0$

Awarded Mar 17 at 5:16

Ethan Chan

2,4821 gold badge25 silver badges48 bronze badges

What is the relation between the linear combination and modular arithmetic?

Awarded Mar 16 at 5:05

combinatorist

1235 bronze badges

Prove that if $\mathfrak A$ contains a bounded set then $\exists M \in \Bbb Z^+$ s.t $A_1 \cap \cdots A_M=∅$

Awarded Mar 16 at 5:05

j.primus

4891 silver badge10 bronze badges

Is using the letters of English in math a universal practice?

Awarded Mar 16 at 5:05

Vaelus

1516 bronze badges

Prove $\beta$ is surjective using commutative group diagram

Awarded Mar 16 at 5:05

kei

32 bronze badges

What is the premium such that it is equal to the $90^{th}$ percentile of the distribution of total claims?

Awarded Mar 14 at 5:21

Vansh Patel

29111 bronze badges

Is Gaussian integral the only one that can be easily solved by this double integral trick?

Awarded Mar 13 at 5:08

Francis Davey

1,1001 gold badge7 silver badges10 bronze badges

Self-attention: rank of matrices

Awarded Mar 12 at 4:46

Kuo

1578 bronze badges

if two sets of vectors are linearly independent; then a set containing all the vectors is linearly independent?

Awarded Mar 10 at 4:08

Myungheon Lee

1,5714 silver badges18 bronze badges

What is the expected value of the largest of the three dice rolls?

Awarded Mar 10 at 4:08

user615536

1094 bronze badges

Substitution for the condition $a^{2}+ b^{2}+ c^{2}+ 3abc= 6$

Awarded Mar 9 at 4:35

Dang Dang

1271 gold badge2 silver badges20 bronze badges

Find the number of solutions of $|\cos(x)|=\cot(x)+\frac{1}{\sin(x)}$ that lie in $[-4\pi,4\pi]$.

Awarded Mar 9 at 4:35

Aadya Chaudhary

5832 silver badges16 bronze badges

Linearization of a max function

Awarded Mar 7 at 4:40

Halil Sen

3371 gold badge3 silver badges12 bronze badges

Taylor Remainder formula for $\sin(x)$

Awarded Mar 6 at 4:03

bkarpuz

8455 silver badges18 bronze badges

Atiyah-Macdonald Exercise 2.15

Awarded Mar 6 at 4:03

John Frank

7112 silver badges13 bronze badges

Why is the expected value of the truncated normal distribution $E(x|x>a) = \mu + \sigma \frac{\phi(\alpha)}{1 -\Phi(\alpha)}$?

Awarded Mar 6 at 4:03

Alex Almeida

33 bronze badges

Combinatorial argument to prove binomial identity

Awarded Mar 6 at 4:03

Klaus

10.7k3 gold badges20 silver badges33 bronze badges

Evaluating $\int \sqrt{1 + t^2} dt$?

Awarded Mar 6 at 4:03

jIvitesha

295 bronze badges

Why is the topological definition of function limit absent from textbooks?

Awarded Mar 6 at 4:03

plante

1051 silver badge5 bronze badges

Probability is unique?

Awarded Mar 6 at 4:03

Ritil

1599 bronze badges

On a possible generalization of Pascal's formula

Awarded Mar 5 at 4:20

Ramen Nii-chan

2,8409 silver badges23 bronze badges

Integral in n-dimensional spherical coordinates

Awarded Mar 5 at 4:20

davidec00

32 bronze badges

coefficent of correlation smaller than 1 proof problem

Awarded Mar 4 at 5:05

Francisco Jácome Maura

1048 bronze badges

The role of non-negativity in Fatou's lemma

Awarded Mar 4 at 5:05

jbuzz

32 bronze badges

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