How this calculation works
Fit the exponent in y=kxᵇ using two positive measurements.
THE FORMULA
b = [ln(y₂)−ln(y₁)]/[ln(x₂)−ln(x₁)]A worked example
Doubling x from 2 to 4 quadruples y, so b=2.
Good to know
The x-values must be different and all measurements positive.
Reference: OpenStax Algebra and Trigonometry (opens in a new tab) ↗
Read the result
Fit the exponent in y=kxᵇ using two positive measurements.
The primary result is labeled “Exponent”. Keep the input definitions in view when comparing this result with another method.
Try a related calculation
The x-values must be different and all measurements positive.
For a related exercise, try the quadratic equation solver.
A few questions, answered
How can I check the default inputs by hand?
Doubling x from 2 to 4 quadruples y, so b=2.
Which rule does this calculator apply?
b = [ln(y₂)−ln(y₁)]/[ln(x₂)−ln(x₁)]