Thread: Problem 21
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Old March 13th, 2007, 12:13 AM
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CaptainBlack CaptainBlack is offline
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Quote:
Originally Posted by CaptainBlack View Post
Let the polynomial:

f(x) = x^n + a_1 x^{n-1} + ... + a_{n-1} x +1

with non-negative real coefficients a_1, .. , a_{n-1} have n real roots.

Prove that f(2) >= 3^n

RonL
A simple example of a polynomial satisfying the conditions of this problem is:

f(x) = (x+1)^2 = x^2 + 2x +1

where n=2, and f(2) = 9 = 3^2 <= 3^2

as expected.

RonL
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