This is documentation for Mathematica 4, which was
based on an earlier version of the Wolfram Language.
View current documentation (Version 11.2)
Wolfram Research, Inc.

Basic OperationsNumerical Equation Solving

1.6.2 Numerical Sums, Products and Integrals

Numerical sums, products and integrals.

Here is a numerical approximation to .

In[1]:= NSum[1/i^3, {i, 1, Infinity}]

Out[1]=

NIntegrate can handle singularities at the end points of the integration region.

In[2]:= NIntegrate[1/Sqrt[x (1-x)], {x, 0, 1}]

Out[2]=

You can do numerical integrals over infinite regions.

In[3]:= NIntegrate[Exp[-x^2], {x, -Infinity, Infinity}]

Out[3]=

Here is a double integral over a triangular domain. Note the order in which the variables are given.

In[4]:= NIntegrate[ Sin[x y], {x, 0, 1}, {y, 0, x} ]

Out[4]=

Basic OperationsNumerical Equation Solving