Difference between revisions of "User:Superagh"

(Theorems worth noting)
(Power mean (weighted)=)
Line 12: Line 12:
 
If <math>x \ge y</math>, then <cmath>pm_x(a_1, a_2, \cdots , a_n) \ge pm_y(a_1, a_2, \cdots , a_n).</cmath>
 
If <math>x \ge y</math>, then <cmath>pm_x(a_1, a_2, \cdots , a_n) \ge pm_y(a_1, a_2, \cdots , a_n).</cmath>
  
====Power mean (weighted)=====
+
====Power mean (weighted)====
 
Statement: Given positive integers, <math>a_1, a_2, a_3 \cdots a_n</math>, and <math>w_1, w_2 \cdots w_n</math> has a positive sum, and integer <math>x</math>, define <math>pm_x(a_1, a_2, \cdots a_n)</math> to be the following expression: <cmath>(w_1a_1^x+w_2a_2^x \cdots w_na_n^x)^{\frac{1}{x}}</cmath> When <math>x\neq0</math>.
 
Statement: Given positive integers, <math>a_1, a_2, a_3 \cdots a_n</math>, and <math>w_1, w_2 \cdots w_n</math> has a positive sum, and integer <math>x</math>, define <math>pm_x(a_1, a_2, \cdots a_n)</math> to be the following expression: <cmath>(w_1a_1^x+w_2a_2^x \cdots w_na_n^x)^{\frac{1}{x}}</cmath> When <math>x\neq0</math>.
  

Revision as of 11:54, 24 June 2020

Introduction

Ok, so inspired by master math solver Lcz, I have decided to take Oly notes (for me) online! I'll probably be yelled at even more for staring at the computer, but I know that this is for my good. (Also this thing is almost the exact same format as Lcz's :P ). (Ok, actually, a LOT of credits to Lcz)

Algebra

Problems worth noting/reviewing

I'll leave this empty for now, I want to start on HARD stuff yeah!

Inequalities

We shall begin with INEQUALITIES! They should be fun enough. I should probably begin with some theorems.

Power mean (special case)

Statement: Given that $a_1, a_2, a_3, ... a_n > 0$, $a_{i} \in \mathbb{R}$ where $1 \le i \le n$. Define the $pm_x(a_1, a_2, \cdots , a_n)$ as: \[(\frac{a_1^x+a_2^x+\cdots+a_n^x}{n})^{\frac{1}{x}},\] where $x\neq0$, and: \[\sqrt[n]{a_{1}a_{2}a_{3} \cdots a_{n}}.\] where $x=0$.

If $x \ge y$, then \[pm_x(a_1, a_2, \cdots , a_n) \ge pm_y(a_1, a_2, \cdots , a_n).\]

Power mean (weighted)

Statement: Given positive integers, $a_1, a_2, a_3 \cdots a_n$, and $w_1, w_2 \cdots w_n$ has a positive sum, and integer $x$, define $pm_x(a_1, a_2, \cdots a_n)$ to be the following expression: \[(w_1a_1^x+w_2a_2^x \cdots w_na_n^x)^{\frac{1}{x}}\] When $x\neq0$.

Combinatorics

Number Theory

Geometry