x_1, x_2, 
-2*x_1^5+x_1^3*x_2^2-x_2^4-2*x_1^2*x_2
-2*x_1^4-4*x_1^3*x_2+5*x_1^2*x_2^2+4*x_1*x_2^3+5*x_2^4+2*x_2^2
