User AlbertH - Mathematics Stack Exchange

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	3,542 reputation	bio	website		visits	member for	2 years
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11

23

votes

2

answers

890

views

Number of local maxima of a function

nov 6 at 11:50 Arnold Neumaier 441

11

20

votes

2

answers

972

views

I'm not sure about this inequality (how to prove or disprove it?)

inequality information-theory entropy

dec 21 at 6:35 Eric 33.3k

11

14

votes

4

answers

850

views

An Inequality problem relating $\prod\limits^n(1+a_i^2)$ and $\sum\limits^n a_i$

inequality

nov 17 at 5:05 y zhao 833

3

12

votes

0

answers

125

views

What are the symmetries of a colored rubiks cube?

group-theory finite-groups recreational-mathematics geometric-group-theory

apr 6 at 17:55 J. M. 39k

2

11

votes

2

answers

497

views

How to introduce stress tensor on manifolds?

differential-geometry classical-mechanics mathematical-physics

aug 16 at 3:31 timur 6,226

9

10

votes

4

answers

493

views

How to prove this inequality? $ab+ac+ad+bc+bd+cd\le a+b+c+d+2abcd$

inequality contest-math

may 18 at 6:24 Inceptio 4,910

6

8

votes

3

answers

428

views

How prove this $(abc)^4+abc(a^3c^2+b^3a^2+c^3b^2)\le 4$

inequality

apr 30 at 9:23 chenbai 838

4

8

votes

2

answers

329

views

Connectedness of the boundary

general-topology

nov 2 at 18:46 TheJoker 1,011

2

8

votes

1

answer

215

views

Sequence of convex functions

convergence convex-analysis

sep 13 at 7:59 Bernard 228

1

6

votes

0

answers

121

views

Question about an upper bound

number-theory inequality

oct 23 at 12:50 Souvik Dey 1,205

1

5

votes

1

answer

87

views

A matrix inequality

linear-algebra matrices

oct 17 at 2:16 Rush 992

3

5

votes

1

answer

270

views

Prove that $\sum_{k=1}^n \frac{2k+1}{a_1+a_2+…+a_k}<4\sum_{k=1}^n\frac1{a_k}.$

inequality contest-math

oct 29 at 22:12 Jack D'Aurizio 2,907

1

4

votes

2

answers

347

views

Could You check whether this expression is nonnegative?

polynomials inequality

aug 7 at 17:00 Johan Löfberg 126

3

4

votes

1

answer

181

views

Second Bianchi identity

homework differential-geometry riemannian-geometry exercises-and-solutions

apr 22 at 20:13 Davide Giraudo 56.3k

1

3

votes

1

answer

85

views

the slope, i.e. the first derivative transforms covariant, some problems with understanding

linear-algebra abstract-algebra

aug 8 at 13:01 rschwieb 21.1k

2

3

votes

2

answers

300

views

Inequality. $a^7b^2+b^7c^2+c^7a^2 \leq 3 $

inequality

sep 21 at 11:09 AlbertH 3,542

1

3

votes

3

answers

250

views

Inequality. $ab^2+bc^2+ca^2 \geq a+b+c.$

inequality

sep 5 at 21:02 Iuli 3,091

3

votes

1

answer

140

views

Inequality $\frac{x^3+1}{\sqrt{x^4+y+z}}+\frac{y^3+1}{\sqrt{y^4+z+x}}+\frac{z^3+1}{\sqrt{z^4+x+y}}\geq 2\sqrt{3}$

inequality

feb 25 at 16:32 Ivan Loh 7,603

1

3

votes

2

answers

212

views

$\frac{a+b-2c}{b+c} + \frac{b+c-2a}{c+a} + \frac{c+a-2b}{a+b} \geq 0$

inequality

oct 23 at 12:48 Souvik Dey 1,205

1

2

votes

0

answers

98

views

Convexity conditions for $f$ and $\dfrac {1} {f}$

real-analysis analysis functional-equations

aug 28 at 8:40 Maria Mikolayevskaya 11

2

votes

0

answers

68

views

Why does the following define a distribution and of which order?

distribution-theory

jun 27 '12 at 18:07 Community♦ 1

3

1

vote

1

answer

192

views

Sum of prime powers equal to a prime power

elementary-number-theory

sep 7 at 3:47 Gerry Myerson 86k

1

vote

0

answers

52

views

An explicit computation of differential geometry

differential-geometry

sep 16 at 5:08 Honghao 185

1

vote

2

answers

135

views

Inequality. $2(x^2+y^2+z^2)^2 \geq 3(x^2y^2+y^2z^2+z^2x^2)+3(x^3y+y^3z+z^3x)$

inequality

sep 25 at 17:17 lab bhattacharjee 29.2k

2

1

vote

1

answer

162

views

Let $a,b,c>0$ and $a+b+c=3$. Find the minimum of $P$.

inequality

sep 29 at 1:52 uforoboa 3,450

1

vote

1

answer

86

views

$f(x)$ is a monotonic function prove the following

sequences-and-series functional-analysis inequality summation

oct 19 at 20:30 M. Strochyk 4,698

2

0

votes

1

answer

254

views

Find number of interesting numbers (China TST 2011)

algebra-precalculus elementary-number-theory contest-math

dec 23 '11 at 13:43 Srivatsan 15.7k

1

-2

votes

2

answers

179

views

Prove two inequalities (sums of square roots of quotients of positive numbers)

inequality

oct 19 at 7:53 Golbez 841

AlbertH

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