Determining Value of Power Series: How & Why?

AI Thread Summary
The discussion focuses on identifying the center of power series, using examples to illustrate the concept. The first series, centered at zero, is represented by the sum of x^n/n!. The second series, centered at -1, involves the expression (-1)^n(x+1)^n, with the ratio test indicating convergence when the limit is less than 1. Participants also briefly discuss the LaTeX notation for the less than symbol. Understanding the center of a power series is crucial for determining its convergence and behavior.
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How do you know what value a power series is centered at?

for example this power series is centered at 0:

\sum_{n=0}^\infty\frac{x^n}{n!}


what makes it centered at zero?



this one is centered at -1:

\sum_{n=0}^\infty{(-1)}^n{(x+1)}^n

the only thing i can discern is that when i perfrom the ratio test, for the secont series, i get this expression:

\lim_{n\rightarrow\infty}\vert{(-1)(x+1)}\\\vert which is supposed to be less than 1.


what's the latex for the lessthan symbol?
 
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I see it now no need to respond. thx
 
what's the latex for the lessthan symbol?

<


\leq for "less than or equal to".
 
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