Difference between revisions of "Radon's Inequality"

(Created page with "Radon's Inequality states: <cmath> \frac{ a_1^{p+1} } { b_1^p } + \frac{ a_2 ^{p+1} } { b_2^p } + \cdots + \frac{ a_n ^{p+1} } { b_n^p } \geq \frac{ (a_1 + a_2 + \cdots+ a_n...")
 
(Proof)
Line 9: Line 9:
 
Just apply Hölder for:
 
Just apply Hölder for:
  
<cmath>(b_1 + b_2 + \cdots+ b_n )^{\frac{p}{p+1}}\left(\frac{ a_1^{p+1} } { b_1^p } + \frac{ a_2 ^{p+1} } { b_2^p } + \cdots + \frac{ a_n ^{p+1} } { b_n^p }\right)^{\frac{1}{p+1}} \geq a_1 + a_2 + \cdots+ a_n  </cmath>
+
<cmath>(b_1 + b_2 + \cdots+ b_n )^{p/(p+1)}\left(\frac{ a_1^{p+1} } { b_1^p } + \frac{ a_2 ^{p+1} } { b_2^p } + \cdots + \frac{ a_n ^{p+1} } { b_n^p }\right)^{1/(p+1)} \geq a_1 + a_2 + \cdots+ a_n  \Leftrightarrow </cmath>

Revision as of 16:18, 14 March 2023

Radon's Inequality states:

\[\frac{ a_1^{p+1} } { b_1^p } + \frac{ a_2 ^{p+1} } { b_2^p } + \cdots + \frac{ a_n ^{p+1} } { b_n^p } \geq \frac{ (a_1 + a_2 + \cdots+ a_n ) ^{p+1} } { (b_1 + b_2 + \cdots+ b_n )^p}\]

It is a direct consequence of Hölder's Inequality, and a generalization of Titu's Lemma.

Proof

Just apply Hölder for:

\[(b_1 + b_2 + \cdots+ b_n )^{p/(p+1)}\left(\frac{ a_1^{p+1} } { b_1^p } + \frac{ a_2 ^{p+1} } { b_2^p } + \cdots + \frac{ a_n ^{p+1} } { b_n^p }\right)^{1/(p+1)} \geq a_1 + a_2 + \cdots+ a_n  \Leftrightarrow\]