MathDB
monic polynomials

Source: Romanian TST 2000

July 17, 2005
algebrapolynomialalgebra proposed

Problem Statement

Let P,QP,Q be two monic polynomials with complex coefficients such that P(P(x))=Q(Q(x))P(P(x))=Q(Q(x)) for all xx. Prove that P=QP=Q.
Marius Cavachi