deriv[?x] is the derivative of unary-scalar-function-quantity ?x {deriv[f[x]] = f'[x]}. Deriv is only defined on continuous functions.
Deriv has the normal algebraic properties of derivatives of real-valued functions; see the axioms for the exact behavior of differentiation with respect to sums and products of unary-scalar-function-quantities.
(Forall (?F ?G ?R)
(=> (And (Unary-Scalar-Function-Quantity ?F)
(Unary-Scalar-Function-Quantity ?G)
(Real-Number ?R))
(And (= (Deriv (+ ?F ?G)) (+ (Deriv ?F) (Deriv ?G)))
(= (Deriv (* ?F ?G))
(+ (* (Deriv ?F) ?G) (* ?F (Deriv ?G))))
(= (Deriv (Expt ?F ?R))
(* ?R (Expt (Deriv ?F) (1- ?R)))))))