Inverse Function Calculator (Linear)
Find the inverse of y = mx+b.
Enter your values
ⓘ Live results
Results
- f^-1(x) formula
- f^-1(x) = (x - 3) / 2
- f^-1(7)
- 2
- Check: f(f^-1(x))
- 7
Quick answer
The inverse of y = mx+b is x = (y-b)/m, i.e. f^-1(x) = (x-b)/m.
f^-1(x) = (x-b)/m
How to use the Inverse Function Calculator (Linear)
- 1Enter the slope m and intercept b of f(x)=mx+b.
- 2The tool swaps x and y and solves for the new y to get the inverse.
- 3Optionally test a value to confirm f(f^-1(x)) returns the original input.
Worked example
Using the values the calculator loads with:
Inputs
- Slope m2
- Intercept b3
- Test x for f^-1(x)7
Results
- f^-1(x) formulaf^-1(x) = (x - 3) / 2
- f^-1(7)2
- Check: f(f^-1(x))7
Frequently asked questions
Does every function have an inverse?
Only one-to-one functions do; linear functions with m≠0 always qualify.
What if m=0?
The function is constant and has no inverse.
About this calculator
- Built and reviewed by James Whitfield · How we build and test calculators
- Report an error
Results are estimates for general information. For medical, legal, structural or financial decisions, confirm with a qualified professional.