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Give an example, if nossible, of power series with the following properties: a) centered at ( z_{0}=3 i ), with radius of convergence ( R=7 ) b) centered at ( z_{0}=1 ) and convergent for all

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Final answer:

A power series is a series of the form Σn=0∞ an(z - z0)n, where z0 is the center, and an are the coefficients. For a power series centered at 3i with a radius of convergence 7, a choice of coefficients could be (-1)n/n!. For a power series centered at 1 and convergent for all complex numbers, a choice of coefficients could be 1 for all n.

Step-by-step explanation:

A power series is a series of the form Σn=0∞ an(z - z0)n, where z0 is the center, an are the coefficients, and z is a complex number. Let's consider the properties mentioned:

a) To find a power series centered at z0 = 3i with a radius of convergence R = 7, we can choose any coefficients an. For example, an = (-1)n / n! would give a power series: Σn=0∞ (-1)n(z - 3i)n.

b) To find a power series centered at z0 = 1 and convergent for all complex numbers, we can choose the coefficients such that the power series converges everywhere. For example, an = 1 for all n would give a power series: Σn=0∞ (z - 1)n.

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