Domain and Range Finder
How It Works
This domain and range finder uses established formulas to provide accurate results.
The basic rule:
- Linear: domain and range are all reals
- Quadratic: domain all reals, range depends on vertex
- Square root: domain requires radicand ≥ 0
- Rational: exclude values making denominator 0
Results are estimates. Consult a professional for critical decisions.
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Explore Allday Everyday Math →Frequently Asked Questions
What is the domain of a function?
The domain is the set of all possible input (x) values for which the function is defined. Look for values that would cause division by zero, negative square roots, or other undefined operations.
What is the range of a function?
The range is the set of all possible output (y) values the function can produce. For a quadratic, the range starts at the vertex. For a square root, the range is always non-negative.
How do I find the domain of a rational function?
Set the denominator equal to zero and solve. Those x-values must be excluded from the domain. The domain is all real numbers except those values.
Does every function have the same domain?
No. Polynomials have domain all reals, but square roots, rational functions, and logarithms all have restricted domains based on their mathematical constraints.