How this calculation works
Integrate three unevenly spaced measurements by joining them with straight segments.
THE FORMULA
Sum Δx × (left y+right y)/2 over adjacent pairsA worked example
The first interval contributes 2 and the second contributes 12.
Good to know
The x-values must increase strictly.
Reference: OpenStax Algebra and Trigonometry (opens in a new tab) ↗
Read the result
Integrate three unevenly spaced measurements by joining them with straight segments.
The primary result is labeled “Signed integral estimate”. Keep the input definitions in view when comparing this result with another method.
Try a related calculation
The x-values must increase strictly.
For a related exercise, try the quadratic equation solver.
A few questions, answered
How can I check the default inputs by hand?
The first interval contributes 2 and the second contributes 12.
Which rule does this calculator apply?
Sum Δx × (left y+right y)/2 over adjacent pairs