I got this question which I don't understand:
"Suppose $x^3 - 2x^2 + a = (x + 2) Q(x) + 3$ where $Q(x)$ is a polynomial. Find the value of a."
I know the identity: $P(x)=A(x)Q(x)+R(x)$, but I'm not sure how to apply it in this question.
Any help would be appreciated, thanks.