SOLUTION: are there any 2 different numbers that when switched with exponents are the same?

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Question 331075: are there any 2 different numbers that when switched with exponents are the same?
Answer by Edwin McCravy(20060) About Me  (Show Source):
You can put this solution on YOUR website!
are there any 2 different numbers that when switched with exponents are the same?

You are asking:

Are there any cases where A%5EB%22%22=%22%22B%5EA when A and B are
different numbers?

The first one that comes to mind is 

2%5E4%22%22=%22%224%5E2

because both sides equal 16.

Another case (using fractions) is 

%289%2F4%29%5E%28%2827%2F8%29%29%22%22=%22%22%2827%2F8%29%5E%28%289%2F4%29%29

We prove that by proving that their logs are equal:

log of the left side

log%28%289%2F4%29%5E%28%2827%2F8%29%29%29%22%22=%22%22%2827%2F8%29log%289%2F4%29%22%22=%22%22%2827%2F8%29log%28%283%2F2%29%5E2%29%22%22=%22%22%2827%2F8%29%2A2%2Alog%28%283%2F2%29%29%22%22=%22%22%2827%2F4%29log%283%2F2%29

log of the right side

log%28%2827%2F8%29%5E%28%289%2F4%29%29%29%22%22=%22%22%289%2F4%29log%2827%2F8%29%22%22=%22%22%289%2F4%29log%28%283%2F2%29%5E3%29%22%22=%22%22%289%2F4%29%2A3%2Alog%28%283%2F2%29%29%22%22=%22%22%2827%2F4%29log%283%2F2%29

So %289%2F4%29%5E%28%2827%2F8%29%29%22%22=%22%22%2827%2F8%29%5E%28%289%2F4%29%29
because the log of the left side equals the log of the right side.

Other solutions are:

%2864%2F27%29%5E%28%28256%2F81%29%29%22%22=%22%22%28256%2F81%29%5E%28%2864%2F27%29%29

%28625%2F256%29%5E%28%283125%2F1024%29%29%22%22=%22%22%283125%2F1024%29%5E%28%28625%2F256%29%29

You can generalize this to:

A=%28%28n%2B1%29%2Fn%29%5En and B=%28%28n%2B1%29%2Fn%29%5E%28n%2B1%29

then A%5EB%22%22=%22%22B%5EA

This can be proved the same way, by showing that the logs of the
left and right sides are equal.

In fact the first solution mentioned above

2%5E4%22%22=%22%224%5E2

is the case of this when n=1

Edwin