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Find a power series that has (2,6) as an interval of convergence.

Short Answer

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Question: Find a power series with an interval of convergence of (2, 6). Answer: f(x) = Σ (x - 4)^n, where the summation is from n = 0 to infinity, and the series converges in the interval (2, 6).

Step by step solution

01

Find the center of the interval of convergence

The center of the interval of convergence lies at the midpoint of (2,6). To find the midpoint, use the formula: midpoint = (starting point + ending point) / 2 midpoint = (2 + 6) / 2 = 4 Hence, the center of the interval of convergence is 4.
02

Find the radius of convergence

The radius of convergence is half the length of the interval. To calculate the radius, use the formula: radius = (ending point - starting point) / 2 radius = (6 - 2) / 2 = 2 So, the radius of convergence is 2.
03

Choose a base function

We choose a base function that converges for the given interval. An appropriate base function would be the geometric series: f(x) = a * (x - c)^n Where c is the center, a is a coefficient (which we can adjust), and n is the term index.
04

Determine the power series

Since we have the center (c = 4), the radius (r = 2), and the base function f(x) = a * (x - 4)^n, we can now construct the power series for the given interval of convergence. Let's use a = 1 (you can choose any non-zero value for a) for simplicity: f(x) = Σ (x - 4)^n, where the summation is from n = 0 to infinity. So, the power series that has (2,6) as an interval of convergence is: f(x) = 1 + (x - 4) + (x - 4)^2 + (x - 4)^3 + ...

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