Can Polynomials of Degree n be Bounded by Constants for Large |z| Values?

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SUMMARY

The discussion focuses on proving that for a polynomial of degree n, P(z), there exist positive constants c and d such that c|z|^n < |P(z)| < d|z|^n for all z with sufficiently large |z|. The approach involves assuming the statement holds for polynomials of degree n-1 and analyzing the polynomial in the form P(z) = az^n + q(z). The solution suggests using the triangle inequality and testing with specific example polynomials to clarify the bounds.

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  • Understanding of polynomial functions and their degrees.
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  • Knowledge of limits and behavior of functions as |z| approaches infinity.
  • Basic experience with mathematical proofs and induction techniques.
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Homework Statement


Show that for a polynomial of degree n, P(z), that for all z with |z| sufficiently large, there are positive constants c,d, s.t. c|z|^n < |P(z)| < d|z|^n


Homework Equations





The Attempt at a Solution


Assume it is true for n-1.
p(z)=az^n+q(z)
Then for z with sufficiently large |z|, there exist e,f s.t. e|z|^(n-1) < |q(z)| < f|z|^(n-1).

No idea how to continue.
 
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Try doing |P(z)| < d|z|^n and c|z|^n < |P(z)| as two different problems. Use triangle inequality. Try it with actual example polynomials first if you're still lost.
 

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