Calculating 13th Taylor Coefficient of f(x)=e^(7x) at x=3

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Homework Help Overview

The discussion revolves around finding the 13th Taylor coefficient of the function f(x) = e^(7x) at x = 3. Participants are exploring the Taylor series expansion and the relevant equations for exponential functions.

Discussion Character

  • Exploratory, Conceptual clarification, Mathematical reasoning

Approaches and Questions Raised

  • The original poster attempts to apply the Taylor series formula for e^x, substituting 7x, but questions the correctness of their resulting expression. Other participants inquire about the value of n that corresponds to the 13th term and the implications of evaluating derivatives of the function at a specific point.

Discussion Status

The discussion is ongoing, with participants questioning the original poster's approach and suggesting a deeper examination of the Taylor series terms and derivatives. There is no explicit consensus yet, but guidance is being offered regarding the evaluation of derivatives and the identification of terms.

Contextual Notes

Participants are navigating the complexities of Taylor series and the specific requirements for determining coefficients, including the evaluation of derivatives at a particular point. The original poster's confusion about their calculations indicates potential misunderstandings about the series expansion process.

cathy
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Homework Statement


Determine its 13^{th} Taylor coefficient of the Taylor Series generated by f at x = 3.
f(x)=e^(7x)


Homework Equations


I used the fact that the series for e^x was ∑x^n/n!



The Attempt at a Solution


Using that above, and replacing x with 7x, shouldn't my answer be 3x*7^13/13!
But that is incorrect? Please advise where I am going wrong? Thank you
 
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cathy said:

Homework Statement


Determine its 13^{th} Taylor coefficient of the Taylor Series generated by f at x = 3.
f(x)=e^(7x)


Homework Equations


I used the fact that the series for e^x was ∑x^n/n!



The Attempt at a Solution


Using that above, and replacing x with 7x, shouldn't my answer be 3x*7^13/13!
But that is incorrect? Please advise where I am going wrong? Thank you

Here's a few questions for you. If$$
f(x) = \sum_{n=0}^\infty \frac{ f^{(n)}(3)}{n!}(x-3)^n$$what value of ##n## gives the 13th term? Once you have that, what is that many derivatives of ##e^{7x}## and what do you get when you evaluate that at ##x=3##?
 
LCKurtz said:
Here's a few questions for you. If$$
f(x) = \sum_{n=0}^\infty \frac{ f^{(n)}(3)}{n!}(x-3)^n$$what value of ##n## gives the 13th term? Once you have that, what is that many derivatives of ##e^{7x}## and what do you get when you evaluate that at ##x=3##?

Isn't it the 13th value of n that gives the 13th term?
 
No. Give it some thought. Write out some terms.
 

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