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scientia
2012-10-15 22:55:57

I have a very weird solution; you probably won't like it but I'll have a go anyway.

Let
.

Then
because
.

Let
.

We find
(just). It follows that
since the quadratic function is strictly increasing for positive x.

The LHS is
and so we are done.

engrymbiff
2012-10-15 04:15:30

Hm... I really cannot solve it, I have a vague memory of how I solved it last time but now I don't have a good clue of how...

bobbym
2012-10-14 01:29:10

Hi anonimnystefy;

I missed that. I am sorry about that. Bob and I had a good discussion on that and it seems better to work backwards in that case. Even though they do work forwards a lot in inequality books.

anonimnystefy
2012-10-14 01:22:40

Hi bobbym

I think what Agnishom wanted to ask you is whether it is okay to start the proof with what we want to prove and work our way to a true statement...

bobbym
2012-10-13 22:48:13

Hi;

This is the problem:

Agnishom
2012-10-13 22:40:04

Hi Bobbym,
Is it okay to start with the thing we are trying to prove?

engrymbiff
2012-10-13 22:28:25

Sorry, that didn't help me..

bobbym
2011-08-20 20:20:36

Hi;

engrymbiff
2011-08-20 19:36:44

How to do this?