[ x^4 - x^3 - 2*x^2 - 3*x - 2, \ x^4 - x^3 + 10*x^2 + 2*x + 15, \ x^4 + 21*x^2 + 25, \ x^4 - 2*x^3 - 26*x^2 - 39*x + 20, \ x^4 - 2*x^3 + 18*x^2 - 17*x - 13 ]