Infinite Degree Polynomials: Describing by Roots

foxjwill
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Homework Statement


Is it possible to describe some infinite degree polynomials by their roots in a way analagous to finite degree polynomials?


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The Attempt at a Solution



I know that, since not all infinite degree polynomials have roots (e.g. the power series representation of e^x), it would not be possible to do so for all of them. But what about polynomials like the power series of sin(x)? I was thinking maybe

\prod^\infty_{n=0} \left ( x^2 - n^2\pi^2 \right )
 
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Is it possible to describe some infinite degree polynomials...
There's no such thing as an infinite degree polynomial. I presume you mean a power series.

If (the analtyic continuation) of your power series is actually meromorphic, then there is a general factorization theorem. See:

http://en.wikipedia.org/wiki/Infinite_product
 
Prove $$\int\limits_0^{\sqrt2/4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx = \frac{\pi^2}{8}.$$ Let $$I = \int\limits_0^{\sqrt 2 / 4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx. \tag{1}$$ The representation integral of ##\arcsin## is $$\arcsin u = \int\limits_{0}^{1} \frac{\mathrm dt}{\sqrt{1-t^2}}, \qquad 0 \leqslant u \leqslant 1.$$ Plugging identity above into ##(1)## with ##u...
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