Taylor series for the following

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SUMMARY

The discussion focuses on finding the Taylor series and radius of convergence for the function \(\mathrm{Ln}\ z\) centered at a specific value. The participant expresses uncertainty about deriving the series and determining the radius of convergence, particularly in relation to the logarithmic function. They mention the relationship \(\mathrm{Log}\ z = \ln{|z|} + i\left(\mathrm{Arg}\ z\right)\) and propose simplifying series terms like \((2z+i)^{2n}\) to analyze convergence. The participant concludes that the radius of convergence, \(R\), is likely 2, pending verification through the Taylor series.

PREREQUISITES
  • Understanding of Taylor and Maclaurin series
  • Familiarity with complex logarithmic functions
  • Knowledge of convergence criteria for power series
  • Basic calculus concepts from Calculus II
NEXT STEPS
  • Study the derivation of Taylor series for complex functions
  • Learn about the radius of convergence and its determination
  • Explore the properties of the natural logarithm in complex analysis
  • Investigate convergence tests for power series
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Students studying calculus, particularly those focusing on complex analysis and series expansions, as well as educators seeking to clarify concepts related to Taylor series and convergence.

TheFerruccio
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I have a couple of general questions, combined with this one specific question

Homework Statement



Find the Taylor or MacLauren series centered about the given value for the following function, determine the radius of convergence

Homework Equations



[tex]\mathrm{Ln}\ z[/tex], 2

The Attempt at a Solution



I know that
[tex]\mathrm{Log}\ z = \ln{|z|} + i\left(\mathrm{Arg}\ z\right)[/tex]

But, I don't know where to go from here, nor do I know how to find a relevant pattern for find the radius of convergence. It might just be an issue of not remembering this from Calc 2.

Also, from earlier questions, if have some series that's in terms of something like [tex]\left(2z+i\right)^{2n}[/tex] Can I just simplify it to be in terms of [tex]2^{2n} \left(z+\frac{i}{2}\right)^{2n}[/tex], then have the radius be the square root of whatever the radius would be if it was in terms of [tex]\left(z+\frac{i}{2}\right)^{n}[/tex]? Then, if the radius is less than 1/2, then it can be determined that the series about the point [tex]z+\frac{i}{2}[/tex] does not converge?
 
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I think, all I have to do is just treat the principle natural log as a regular natural log, not splitting it up into anything the definition calls for, then just evaluate it that way, with the radius of convergence being from the point of evaluation to where the natural log ceases to exist. In this case, by observation, R would be 2, but I'll verify it with a Taylor series.
 

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