- #1
Whovian
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Homework Statement
I'm trying to prove, for part of a homework problem, that if the ratio of two polynomials ##p## and ##q## with real coefficients is a polynomial, then all of its coefficients are real.
Homework Equations
N/A
The Attempt at a Solution
Well, we can first note that for real ##x##, ##p\left(x\right)## and ##q\left(x\right)## are real, and so ##\lim\limits_{a\to x}\left(\dfrac{p\left(a\right)}{q\left(a\right)}\right)## is real (remember that ##\dfrac pq## is a polynomial, and thus ##p## is divisible by ##q##.) I seem to be stuck here proving that any polynomial ##\mathbb{R}\to\mathbb{R}## has real coefficients. Any ideas?
EDIT: Oh wait. I think maybe induction and differentiation might help?
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