finds the largest domain of definition of the real function f of the variable x.


considers f to be a function with arguments and values in the domain dom.


finds the largest domain of definition of the mapping funs of the variables vars.


finds the domain of funs with the values of vars restricted by constraints cons.

Details and Options

  • funs should be a list of functions of variables vars.
  • Possible values for dom are Reals and Complexes. The default is Reals.
  • If dom is Reals then all variables, parameters, constants, and function values are restricted to be real.
  • cons can contain equations, inequalities, or logical combinations of these.
  • The following options can be given:
  • GeneratedParametersChow to name parameters that are generated
    MethodAutomaticwhat method should be used
    WorkingPrecisionAutomaticprecision to be used in computations


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Basic Examples  (2)

Find the largest domain of definition of a real function:

The largest domain of definition of a complex function:

Scope  (4)

Real univariate functions:

Domain restricted by constraints:

Complex univariate functions:

Real multivariate functions:

Complex multivariate functions:

Options  (2)

GeneratedParameters  (1)

FunctionDomain may introduce new parameters to represent the domain:

Use GeneratedParameters to control how the parameters are generated:

Method  (1)

By default, domains of real univariate functions are given in a reduced form:

Domains of other functions are not reduced:

Use Method to specify whether the domain should be given in a reduced form:

Introduced in 2014