In the case of , the factors, and the methods for computing them, depend strongly on . Over the complex numbers, the irreducible factors (those that cannot be factorized further) are all of degree one, while, over the real numbers, there are irreducible polynomials of degree 2, and, over the rational numbers, there are irreducible polynomials of any degree. For example, the polynomial formula_31 is irreducible over the rational numbers, is factored as formula_32 over the real numbers and, and as formula_33 over the complex numbers.