#maclaurin series of e^(e^x) in terms of x

45 messages · Page 1 of 1 (latest)

latent pagoda
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Can someone explain how to evaluate this in terms of x?

slim martenBOT
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latent pagoda
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@helper

subtle mist
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You can evaluate it as a double series

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Like $e^{e^x}=\sum_{n=0}^{\infty} \frac{e^{nx}}{n!}$

latent pagoda
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Like this?

astral sorrelBOT
latent pagoda
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If I’m only doing up to x^2

subtle mist
latent pagoda
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Finding the series up to the coefficient of x^2

subtle mist
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Are you doing a Taylor expansion like e^x=1+x+x^2/2 + o(x^2)?

latent pagoda
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Yeah

subtle mist
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Ohh I see

latent pagoda
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That’s what I did

subtle mist
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If you are doing till second order then that’s correct

latent pagoda
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Okay perfect

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Was just doing it for understanding

subtle mist
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Don’t forget that the terms of power >2 are négligeable and you can also use Taylor young’s formula

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It’s another possibility

latent pagoda
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I don’t know that

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It’s not in my specification of learning

subtle mist
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Ok no problem

latent pagoda
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But thank you for the help

final matrix
latent pagoda
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I know but the question says I have to do it that way

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Hold on

final matrix
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interesting

subtle mist
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well you said yourself Taylor you isn’t possible

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*Taylor young

final matrix
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this is also the bell numbers EGF

latent pagoda
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Sorry you’re gonna have to explain 😭

final matrix
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not too relevant, just happens that a certain sequence bn which counts number of set partitions, appears here

subtle mist
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Isnt it like the generator function or something ? Can’t remember

dull snow
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@latent pagoda I think that’s right

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The “x+1/2 x^2 + 1/6 x^3” becomes ur “x”

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U sub that into the maclaurin expansion

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Neglecting all the terms higher than x^3 of course

zealous stream
latent pagoda