public static double FirstDerivative(
	Func<double, double> function,
	double xPoint,
	double h = 1E-14
)

Public Shared Function FirstDerivative ( 
	function As Func(Of Double, Double),
	xPoint As Double,
	Optional h As Double = 1E-14
) As Double

public:
static double FirstDerivative(
	Func<double, double>^ function, 
	double xPoint, 
	double h = 1E-14
)

static member FirstDerivative : 
        function : Func<float, float> * 
        xPoint : float * 
        ?h : float 
(* Defaults:
        let _h = defaultArg h 1E-14
*)
-> float