Chapter 13. Calculus (.NET, C#, CSharp, VB, Visual Basic, F#)
NMath provides classes
for encapsulating functions of one variable, 
. Once constructed, function
objects enable you to:
● evaluate a function at a given x-value or vector of x-values;
● integrate a function over a given interval;
● compute the derivative of a function at a given x-value;
● manipulate functions algebraically.
This chapter describes how to create and manipulate function objects.