Poly function of degree n with no roots

  • Thread starter Dafe
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  • #1
Dafe
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Homework Statement



(a) If n is even find a polynomial function of degree n with n roots.
(b) If n is odd find one with only one root.

Homework Equations


N/A


The Attempt at a Solution



If by no roots, they mean no real roots then I guess:
[tex] f(x) = x^n+1[/tex] would work for both even and odd n's.
The roots would be i and -i if n is even, and -1, and two complex roots if it's odd..

Suggestions are very welcome :)
 

Answers and Replies

  • #2
HallsofIvy
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Yes, that looks to me to be a perfectly good answer. However, "The roots would be i and -i if n is even, and -1, and two complex roots if it's odd" is true only for n= 2 and 3. For general n, if n is even, then all n roots are non-real, i and -i being two of the. If n is odd, -1 is a root and the other n-1 roots are non-real.
 
  • #3
Dafe
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Ah, I should have stated that, thank you.
You are usually the one that answers all questions I post around here. It's incredible that you do that for free..You should set up a paypal account :)
Thanks again.
 

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