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Christophicus
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Obviously when a=b for any integer.

How can you find out all solutions?

Something to do with logs?
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RichE
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(Original post by Widowmaker)
Obviously when a=b for any integer.

How can you find out all solutions?

Something to do with logs?
The only distinct postive integer pair solving this is 2^4=4^2.

More generally, for reals, if you rewrite the equation as

lna/a = lnb/b

and sketch the graph of y = lnx/x you'll see that for every b>1/e there is a unique a in the range 1<a<1/e such that a^b = b^a.
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[email protected]
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http://www.qbyte.org/puzzles/p048s.html
integer sol's is in there
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Euler
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(Original post by Widowmaker)
Obviously when a=b for any integer.

How can you find out all solutions?

Something to do with logs?
I had this question for my interview test at Trinity...
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~Raphael~
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(Original post by Euler)
I had this question for my interview test at Trinity...

What did you say?
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Euler
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(Original post by ~Raphael~)
What did you say?
the only integer solution is 2^4=4^2

said something like take logs, and draw the graph of the result and observe some blah!

it was partially correct...
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