Result
Enter values and select Calculate.
Method and worked example
Set y equal to the function, solve for x, then exchange x and y. A fractional-linear function requires ad − bc ≠ 0 and excludes denominator-zero inputs.
Example: For f(x)=2x+3, f⁻¹(x)=(x−3)/2.
Assumptions and limitations
No general symbolic parser or automatic branch restriction for non-one-to-one functions.
Calculations run in this browser. The page does not upload entered values, add them to URLs, or save them to browser storage.
Common checks
- Confirm coefficient signs and the selected mode before interpreting the result.
- Remember that interval endpoints depend on strict versus inclusive comparisons or bounds.
- Keep full precision through the method; rounded display values are for reading.
Method source
OpenStax mathematics reference. The interface and calculations are independently implemented.
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