Exponents Homework: Proving Inequality of 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 postive 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 x^{\frac{1}{x}} maximized? I think it's e.
 


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

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


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
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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