if a function is defined by an equation, explain how to find its domain.
has no value for f(0). Thus, the set of all real numbers, R, cannot be its domain. In cases like this, the function is either defined on R\{0} or the gap is plugged by explicitly defining f(0). If we extend the definition of f to. then f is defined for all real numbers, and its domain is R {\displaystyle \mathbb {R} } .