FRT FRS of degree 2
by adityaguharoy, Dec 12, 2016, 4:40 PM
Here I am going to discuss a new theory and a quite useful way of solving inequality problems in which we use the Rearrangement inequality as a tool to develop a new type of inequality the Functional Reciprocal Sum inequality which is described as follows :
This work is authored by Aditya Guha Roy
Alternatively one can find something relevant over here.
(Many thanks to Daniel Sitaru)
http://www.ssmrmh.ro/wp-content/uploads/2016/12/FUNCTIONAL-RECIPROCAL-THEORY-DEGREE-2.pdf
If for a function
over some subset
we have
the pairs
and
are similarly sorted then we say that
is p-monotone over
.
And if ,
the pairs
and
are oppositely sorted then we say that
is i-monotone over
.
With this we have some lemmas :
Lemma 1 : (First Functional Reciprocal Sum Inequality (FRS 1)
If
is p-monotone over
and
is i-monotone over
then, we have the following inequality :

Sketch of Proof
Problems
This work is authored by Aditya Guha Roy
Alternatively one can find something relevant over here.
(Many thanks to Daniel Sitaru)
http://www.ssmrmh.ro/wp-content/uploads/2016/12/FUNCTIONAL-RECIPROCAL-THEORY-DEGREE-2.pdf
If for a function








And if ,






With this we have some lemmas :
Lemma 1 : (First Functional Reciprocal Sum Inequality (FRS 1)
If





Sketch of Proof
Use Rearrangement inequality over
to establish the inequality
and
use Rearrangement inequality over
to establish the inequality
and
can be established using Rearrangement inequality or AM-GM inequality.


use Rearrangement inequality over

to establish the inequality

and

Problems
We can solve many problems using this Lemma:
Problem 1
For all positive reals
and all non-negative real numbers
we have the following :

Problem 2
For all positive
and all nonnegative
we have

Problem 3 ([aka., CeuAzul] )
For all acute angles

Problem 4
For all
we have

Problem 1
For all positive reals



Problem 2
For all positive



Problem 3 ([aka., CeuAzul] )
For all acute angles


Problem 4
For all


This post has been edited 4 times. Last edited by adityaguharoy, Mar 3, 2017, 3:24 AM