x⁴-2004x²+2005x-2004
=x⁴+x-2004x²+2004x-2004
=x(x³+1)-2004(x²-x+1)
=x(x+1)(x²-x+1)-2004(x²-x+1)
=(x²-x+1)[x(x+1)-2004]
=(x²-x+1)(x²+x-2004)谢谢了~别客气