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

Can we find a sequence, say p_j(z) such that p_j ---> 1/z uniformly for z is an element of an annulus between 1 and 2, that is 1 < abs(z) < 2?

Then i am asked to do the same thing but for p_j ---> sin(1/z^2).

2. Relevant equations

Not too sure about this, maybe Taylor series/Laurent series expansions.

3. The attempt at a solution

So while I have no definite path yet set on proving this what I do have are a few thoughts. On this annulus 1/z is analytic because the point z = 0 is not contained. Also, we can write a Taylor/Laurent series expansion for 1/z.

However, I do not believe that we are able to do the same thing for the sin sequence because we end up with a larger numerator term which blows up and cause the series to diverge. However, against z = 0 is not contained here so maybe that is false? Am I thinking about this correctly or am I a fool?

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# Homework Help: Polynomial sequence uniformly convergent on annulus

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