Review for quiz 2

Published

October 18, 2026

We have our first quiz in just a couple of days - on Wednesday, October 21st. The problems on the quiz will be a subset of variations of these problems.

Problems

  1. Write down the following definitions

    1. Convergent series
      Definition 4.1.12 of our text
    2. Absolute convergent series
      Definition 4.1.13 of our text
  2. Find the largest open disks on which each of the following series converges:

    1. \(\displaystyle \sum_{n=1}^{\infty} \frac{n^2}{n!} z^n\)
    2. \(\displaystyle \sum_{n=1}^{\infty} \frac{n^3}{3^n} (z-(4+3i))^n\)

    Note that degenerate cases, such as a single point or all of \(\mathbb{C}\) are possible.

  3. Use the geometric series formula to evaluate the following series:

    1. \(\displaystyle \sum_{n=0}^{\infty} \frac{1}{(1+i)^n}\)
    2. \(\displaystyle \sum_{n=3}^{\infty} \frac{2^{n+2}}{(3+4i)^n}\)
  4. Starting with the series representation \[ \arctan(z) = \sum_{n=0}^{\infty} (-1)^n \frac{z^{2 n+1}}{2 n+1}, \] find a power series representation of \[ \int \arctan(z^2) \, dz. \] What is the largest open disk on which your power series is valid?

Questions

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