Using Liouville's Theorem to Show that Bounded Entire Functions are Polynomials

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The discussion revolves around proving that a bounded entire function is a polynomial of degree less than or equal to m, given the condition |f(z)| ≤ M|z|m for |z| ≥ R. Participants suggest using Liouville's theorem, which states that a bounded entire function must be constant, to support the argument. The idea is to analyze the behavior of the function using its Taylor expansion and the ML inequality, particularly for fixed radius balls. There is a consensus that the boundedness condition implies that the function cannot grow faster than a polynomial of degree m. Overall, the conversation emphasizes the application of Liouville's theorem in this context.
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Let f: ℂ→ ℂ be an entire function. If there is some nonnegative integer m and positive constants M,R such that

|f(z)| ≤ M|z|m, for all z such that |z|≥ R,

show that f is a polynomial of degree less that or equal to m.


im really lost on this question. i feel like because there is an inequality sign that i may have to use the ML inequality but I've tried that and i didnt get very far? am i going in the right direction?

any help or hints would be appreciated :-)

thanks
 
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It seems like it may be an application of Liouville. Every time you have entire and bounded together, consider Liouville's theorem.

Maybe you can argue that for balls of fixed radius 1,2,3,.. |f| is bounded if the degree of the poly. is ≥ m, by , e.g., consider the Taylor expansion for f , which is global in ℂ , but let me think about it some more.
 
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