Online function domain calculator for students and teachers. Supports rational, root, logarithmic, and composite functions; it returns the domain and each restriction—ideal for learning functions.
Show more ▾
📖 Tutorial | ❓ FAQ
Domain: the set of x-values for which the function is defined
📖 Definition of a function
Let A and B be non-empty sets of numbers. If each x in A is paired by a fixed rule f with exactly one value f(x) in B, then f: A → B is a function from A to B.