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
 
Thread 'Erroneously  finding discrepancy in transpose rule'
Obviously, there is something elementary I am missing here. To form the transpose of a matrix, one exchanges rows and columns, so the transpose of a scalar, considered as (or isomorphic to) a one-entry matrix, should stay the same, including if the scalar is a complex number. On the other hand, in the isomorphism between the complex plane and the real plane, a complex number a+bi corresponds to a matrix in the real plane; taking the transpose we get which then corresponds to a-bi...

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
Views
3K
  • · Replies 1 ·
Replies
1
Views
2K