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I know that $x e^x = e$ means $x = 1$, but how do you solve for it?

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    What have you tried? Can you rule out some ranges for $x$? Have you tried playing with logarithms (the natural thing to do)?2010-11-28
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    @Raskolnikov: the problem is to show that x = 1 is the only (say, real) solution. I do not think "duh" is a constructive comment.2010-11-28
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    So guys, correct me if I am wrong: In many ways we can *prove* that x = 1, but given "xexp(x) = e", it is impossible to solve for x, that is, write x = {some formula} = ... = 1.2010-11-28
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    @Perfecto: essentially, yes.2010-11-29
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    Are we going to debate the term "closed form" again?2010-11-29
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    You have to use a new function, the Lambert W function. Try it in Maple, Mathematica or Wolfram Alpha.2018-10-09

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