(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

This is not so much an entire problem I need help with but just a part.

It is a power series where after you do the ratio test, you end up with |4x^(2)| < 1, so |x^(2)| < 1/4.

Since the radius of convergence is |x-a| < R, I end up with -1/4 < x^(2) < 1/4, but because you cannot take the square root of a negative number, I get 0 <= x < 1/2

So how would I describe the Radius of Convergence in this case? Thanks in advance.

2. Relevant equations

|x-a| < R (but in this case after the ratio test you end up with 4x^(2) < 1)

3. The attempt at a solution

See what I wrote in A

EDIT: You can delete this post, I was just spacing on some primary algebra :(

|x^2| < 1/4 -----> |x| < 1/2, -1/2 < x < 1/2 so radius of convergence is 1/2

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# Homework Help: Question on Radius of Convergence for values of x, when f(x) is x^2

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