All about flooble | fun stuff | Get a free chatterbox | Free JavaScript | Avatars    
perplexus dot info

Home > Just Math
Tricky function composition (Posted on 2021-05-19) Difficulty: 3 of 5
Find all pairs of polynomials P(x),Q(x) with integer coefficients such that P(Q(x)) = (x - 1)(x - 2)...(x - 9) for all real numbers x

No Solution Yet Submitted by Danish Ahmed Khan    
No Rating

Comments: ( Back to comment list | You must be logged in to post comments.)
Some Thoughts Some simple pairs Comment 1 of 1
Call G(x)= (x - 1)(x - 2)...(x - 9)

The simplest solutions are Q(x)=G(x), P(x)=x 
or Q(x)=x, P(x)=G(x)

But then you can make P(x)=G(x-n), Q(x)=x+n for any integer n.
This is just a shift.

You could use any invertible function that covers the reals.  But to keep then polynomials with integer coefficients is more limiting.

I'd love to see both P and Q be third degree polynomials, but nothing I've tried seems to work.


  Posted by Jer on 2021-05-20 14:50:14
Please log in:
Login:
Password:
Remember me:
Sign up! | Forgot password


Search:
Search body:
Forums (0)
Newest Problems
Random Problem
FAQ | About This Site
Site Statistics
New Comments (13)
Unsolved Problems
Top Rated Problems
This month's top
Most Commented On

Chatterbox:
Copyright © 2002 - 2024 by Animus Pactum Consulting. All rights reserved. Privacy Information