Finding a power series expansion for a definite integral

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SUMMARY

The discussion focuses on finding a power series expansion about x = 0 for the function defined by the definite integral f(x) = ∫(1 - e^(-sx))/s ds from 0 to 1. Participants encountered challenges due to the integral being undefined at x = 0. A successful approach involves substituting the Taylor series for e^(-sx) into the integrand, simplifying, and then integrating the resulting series. This method effectively resolves the initial dead ends faced by the participants.

PREREQUISITES
  • Understanding of power series expansions
  • Familiarity with Taylor series
  • Knowledge of definite integrals
  • Basic calculus concepts
NEXT STEPS
  • Study the derivation and application of Taylor series for exponential functions
  • Learn techniques for integrating power series term-by-term
  • Explore convergence criteria for power series
  • Investigate other methods for handling improper integrals
USEFUL FOR

Students and educators in calculus, mathematicians working with series expansions, and anyone interested in advanced integration techniques.

Szichedelic
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Homework Statement



Find a power series expansion about x = 0 for the function

f(x) = ^{1}_{0}\int\frac{1 - e^{-sx}}{s} ds


Homework Equations



The power series expansion for a function comes of the form f(x) = ^{\infty}_{0}\sum a_{k}x^{k}


The Attempt at a Solution



I've tried several things to start off with but quickly end up hitting a dead end road. First, I tried just simply taking the integral, but quickly found it isn't defined at 0 (hence why they are asking me to find a power series expansion for it). Then, I tried finding a power series expansion for the innerpart of the integral and ran into the same problem.
 
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Szichedelic said:

Homework Statement



Find a power series expansion about x = 0 for the function

f(x) = ^{1}_{0}\int\frac{1 - e^{-sx}}{s} ds

Homework Equations



The power series expansion for a function comes of the form f(x) = ^{\infty}_{0}\sum a_{k}x^{k}

The Attempt at a Solution



I've tried several things to start off with but quickly end up hitting a dead end road. First, I tried just simply taking the integral, but quickly found it isn't defined at 0 (hence why they are asking me to find a power series expansion for it). Then, I tried finding a power series expansion for the innerpart of the integral and ran into the same problem.

Did you try substituting the Taylor series (as a function of x) for ##e^{-sx}## in the integrand, simplifying and integrating?
 
Yeah, I figured that out shortly after I posted this. Can't believe I overlooked that! Thanks!
 

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