[x^4 + 3*x^2 - 12, \
 x^4 - x^3 + 6*x^2 + 8*x - 5, \
 x^4 - 6*x^2 - 11*x - 3, \
 x^4 - x^3 - 4*x^2 - 5*x + 25, \
 x^4 - x^3 + 3*x^2 + x + 20, \
 x^4 - 2*x^3 + 3*x^2 - 2*x + 4]