1. x4 + 2008x2 + 2007x + 2008
= (x4 + x2 + 1) + (2007x2 + 2007x + 1)
= (x2 + x + 1)(x2 - x + 1) + 2007(x2 + x + 1)
= (x2 + x + 1)(x2 - x + 2008)
2. x4 - 6x3 + 12x2 - 14x - 3
= x4 - 2x3 + 3x2 - 4x3 + 8x2 - 12x + x2 - 2x + 3
= x2(x2 - 2x + 3) - 4x(x2 - 2x + 3) + (x2 - 2x + 3)
= (x2 - 2x + 3)(x2 - 4x + 1)