PNT wrote:No it is not, try long division.
I tried to use this method,
Assuming (x^2+x+1)(ax+b) = ax^3+(a+b)x^2+(a+b)x+(b+1) = X^3+X+1,
then by checking X^3 and the constant, we got a=3n+1 , b = 3m (n,m are of Z). then (a+b)X^2 --> X^2 !=0 which contradicts the assumption.
is this logic ok or any better solution to check?