Author Topic: 2.4  (Read 393 times)

serena li

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2.4
« on: March 01, 2020, 10:18:13 PM »
For the question asking to find the power-series expansion about the given point for the function and find the largest disc where the series are valid, I am confused about how to find the valid largest disc. Thank you so much.

Victor Ivrii

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Re: 2.4
« Reply #1 on: March 07, 2020, 08:08:06 AM »
Either investigate the power series or to use theorem that if $f$ is analytic in some disc $D(z_0,r)$, then the expansion at its center $z_0$ converges in this disc.