Observed arrival · 2026-10-30
Calculus, Learned by Moving Things
An interactive introduction to limits, slopes, derivatives, area, and the fundamental theorem of calculus.
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- Learners meeting introductory calculus concepts
- Worth noticing
- The Riemann-sum section offers left-edge, middle, and right-edge rectangle choices, with a control to increase the number of rectangles.
Field notes
The five sections build from a removable hole in (x² − 1) / (x − 1) to the relationship between an accumulated-area function and its source function. Controls described on the page let learners move points, sweep across a graph, and change rectangle placement and count; short questions check understanding along the way.
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