Suppose a1,a2,a3,a4 are distinct integers and P(x) is a polynomial with integer coefficients satisfying P(a1)=P(a2)=P(a3)=P(a4)=1.
(a) Prove that there is no integer n such that P(n)=12.
(b) Do there exist such a polynomial and an integer n such that P(n)=1998? polynomialInteger Polynomialalgebra