List questions from geometric-inequalities | MathQA

Convex polygons - For $n>3$, $\sum_{i=1}^{n} \cos\theta_i < \cos\left(\sum_{i=1}^{n} {\theta_i}\right)$

Published on 30 Aug 2022 - 15:45

$\cos(a)+\cos(b)-\cos(a+b)\geq 1$

Published on 01 Sep 2022 - 21:01

$ab+bc+ca \le 4{\sqrt 3}\Delta$ for a triangle with sides $a$, $b$ and $c$ with area $\Delta$

Published on 24 Sep 2022 - 15:26

Prove that $x\sin A+y\sin B+z\sin C\leqslant \frac{\sqrt{\left( x^2+k \right) \left( y^2+k \right) \left( z^2+k \right)}}{k}$

Published on 24 Sep 2022 - 16:22

Showing $(4H-2L)e^{\frac{H+L}{k}}-2(H-L)(e^{H/k}+e^{\frac{H+2L}{k}})-L(e^{2H/k}+e^{2L/k})\geq 0$ for $k>0$, $H>0>L$, and $H+L>0$

Published on 04 Oct 2022 - 18:24

Norm inequality for Banach Lattices

Published on 25 Mar 2026 - 9:25

Feasibility - When is a set defined by linear inequalities empty (in $\mathbb{R}^n$, with $n \geq 4$)?

Published on 03 Nov 2022 - 18:30

Proving a simple vector inequality

Published on 11 Nov 2022 - 0:27

Prove that the inequality is valid if $x,y,z$ are positive numbers and $xyz=1.$

Published on 05 Dec 2022 - 20:57

Prove or disprove that the inequality is valid if $x,y,z$ are positive numbers and $xyz=1$.

Published on 22 Dec 2022 - 17:22

Prove or disprove the inequality if $a,b,c>0$, $a \geq b+c$.

Published on 22 Dec 2022 - 18:15