\(x^4+2004x^2+2003x+2004\)
\(=x^4-x+2004x^2+2004x+2004\)
\(=x\left(x^3-1\right)+2004\left(x^2+x+1\right)\)
\(=x\left(x-1\right)\left(x^2+x+1\right)+2004\left(x^2+x+1\right)\)
\(=\left(x^2+x+1\right)\left(x^2-x+2004\right)\)
\(x^4+2004x^2+2003x+2004\)
\(=x^4+2004x^2+2004x-x+2004\)
\(=\left(x^4-x\right)+2004\left(x^2+x+1\right)\)
\(=x\left(x^3-1\right)+2004\left(x^2+x+1\right)\)
\(=x\left(x-1\right)\left(x^2+x+1\right)+2004\left(x^2+x+1\right)\)
\(=\left(x^2+x+1\right)\left(x^2-x+2004\right)\)