Power Series Representation of e^(sin(x))

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Homework Help Overview

The problem involves finding the power series representation of the function f(x) = e^(sin(x)). The context is centered around series expansions and their manipulation in calculus.

Discussion Character

  • Exploratory, Mathematical reasoning, Problem interpretation

Approaches and Questions Raised

  • Participants discuss substituting sin(x) into the exponential series and express uncertainty about the correct formulation of the series. Some attempt to derive the nth term but struggle to find a closed form. Others suggest expanding sin(x) as a series to find initial terms.

Discussion Status

The discussion is ongoing, with participants sharing their attempts and expressing concerns about the complexity of the problem. There is no explicit consensus, but some productive lines of reasoning have been suggested, particularly regarding the expansion of sin(x).

Contextual Notes

One participant mentions an impending exam, indicating a time constraint that may affect the depth of exploration. There is also a reference to the notation used for summation, which suggests a need for clarity in mathematical expressions.

mouser
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Homework Statement



Find the power series representation of the following:

f(x) = e^(sin(x))

Homework Equations



I know this to be true:

e^x = (Inf Sum, n=0) (x^n/n!)

The Attempt at a Solution



So, in substituting sin(x) for x, I get:

e^(sin(x)) = 1 + sin(x)/1 + sin(x)/2 + sin(x)/6 + ...

or

e^(sin(x)) = (Inf Sum, n=0) ((sin(x))^n/n!)

Not sure where I'm going wrong here, so a nudge in the right direction would be greatly appreciated. Thanks in advance!
 
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Does anyone have any advice here? I have an exam tomorrow, for which I am almost fully prepared. With my luck though, this problem will be on the exam and I'll be screwed!

Any help would be much appreciated!
 
Also, by (Inf Sum, n=0), I meant [tex]\sum[/tex]

Thanks
 
I think everybody knows what you mean. You presented the problem pretty clearly. But I don't know how to express the nth term of your series in any nice closed form. If nobody answered they probably don't either. It's pretty easy to find the first few terms by expanding sin(x) as a series. But I don't know the general term.
 
In short, we have to simplify this:

[tex]\sum_{r=0}^{\infty}\frac{1}{r!}(\sum_{t=0}^{\infty} \ \frac{(-1)^tx^{2t+1}}{(2t+1)!})^r[/tex]

That looks pretty horrendous to begin with.
 
Maybe that IS the answer...
 
Except, incorporate the 'r' as t's
 

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