MHB Polynomial with integer coefficients

Click For Summary
The discussion centers on proving that for three distinct integers \(a\), \(b\), and \(c\), a polynomial \(P\) with integer coefficients cannot satisfy the conditions \(P(a)=b\), \(P(b)=c\), and \(P(c)=a\) simultaneously. The key argument involves analyzing the implications of these conditions on the polynomial's behavior and the properties of integers. It is established that such a polynomial would lead to contradictions regarding the distinctness of \(a\), \(b\), and \(c\). Therefore, the conclusion is that no polynomial with integer coefficients can meet all three conditions at once. This result highlights the limitations of polynomial mappings in relation to distinct integers.
anemone
Gold Member
MHB
POTW Director
Messages
3,851
Reaction score
115
Let $a,\,b,\,c$ be three distinct integers and $P$ be a polynomial with integer coefficients. Show that in this case the conditions $P(a)=b,\,P(b)=c,\,P(c)=a$ cannot be satisfied simultaneously.
 
Mathematics news on Phys.org
The polynomial is P(x)

we have m-n divides P(m) - p(n)

Let the given condition is true

So $a-b | P(a) - p(b)$

or $a-b | b- c$

Similarly

$b - c | c- a$

And $ c- a | a - b$

From above 3 have

$a-b | b-c | c- a | a-b$So all are same and hence a = b= c which is a contradiction.so condition can not be satisfied simultaneously
 
Here is a little puzzle from the book 100 Geometric Games by Pierre Berloquin. The side of a small square is one meter long and the side of a larger square one and a half meters long. One vertex of the large square is at the center of the small square. The side of the large square cuts two sides of the small square into one- third parts and two-thirds parts. What is the area where the squares overlap?

Similar threads

  • · Replies 14 ·
Replies
14
Views
2K
  • · Replies 1 ·
Replies
1
Views
1K
Replies
3
Views
1K
Replies
2
Views
1K
  • · Replies 8 ·
Replies
8
Views
3K
  • · Replies 26 ·
Replies
26
Views
3K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 48 ·
2
Replies
48
Views
3K
  • · Replies 1 ·
Replies
1
Views
2K