Exponents Homework: Proving Inequality of Positive Integers

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Homework Help Overview

The problem involves proving an inequality related to the expressions m^(1/n) and n^(1/m) for positive integers m and n, specifically that one of these expressions is always less than or equal to 3^(1/3).

Discussion Character

  • Exploratory, Assumption checking

Approaches and Questions Raised

  • Participants discuss different cases for the relationship between m and n, including equality and inequality. There is a suggestion to consider the maximization of the function x^(1/x) and its relevance to the problem.

Discussion Status

The discussion is ongoing with participants exploring different cases and hints regarding the maximization of certain functions. There is no explicit consensus yet, but some guidance has been offered regarding analyzing the behavior of the function involved.

Contextual Notes

Participants are considering the implications of the maximum value of the function x^(1/x) and its relationship to the constant e, as well as the behavior of the function on positive integers.

furnis1
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Homework Statement




Hey guys, I am having difficulty with the following problem:

"If m and n are two positive integers, prove that one of m^(1/n) or n^(1/m) is always less than or equal to 3^(1/3)"

Any idea of how to go about this?


Homework Equations





The Attempt at a Solution

 
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Hmm...

Well here is what could happen:

m=n
m>n or
m<n

The last two cases can be treated as one.

One more hint: for what value of x is [tex]x^{\frac{1}{x}}[/tex] maximized? I think it's e.
 


futurebird said:
Hmm...
One more hint: for what value of x is [tex]x^{\frac{1}{x}}[/tex] maximized? I think it's e.

I don't see how e can be useful since [tex]3^{1/3} \leq e[/tex]
 


If you know where the max value is you should be able to locate the max value for the function on the positive integers by looking at where the function is increasing and decreasing.

Then deal with the case where m != n
 

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