x_PA:= PolynomialAlgebra(FiniteField(5));; x_f:= Coerce(x_PA,X^2+2);; x_PSR:= PowerSeriesRing(FiniteField(5),x_f);; x_PSRx:= PolynomialAlgebra(x_PSR);; x_ff:= x_PSRx.1^2+Element(x_PSR,[1,2,3])*x_PSRx.1-2; Derivative(x_ff);