## Mathematical Analysis## Integral Calculus |

## Are there double and triple integrals? |

Yes, there are double and triple integrals—and even multiple integrals in equations (∫∫, ∫∫∫, and so on). For example, the integration of a function of three variables, *w = f(x, y, z)*, over a three-dimensional region *R* in *xyz*-space (three-dimensional space) is called a triple integral. The notation is as follows:

To compute the iterated integral, we need to integrate with respect to *z* first, then *y*, then *x*. And when we integrate with respect to one variable, all the other variables are assumed to be constant.