Four triangles in one square, slid into new places: the empty space shows a² + b² = c².

From OpenStax Prealgebra 2e, 9.3 and cut-the-knot proofs #4 and #9.

AvailableFull-film skill

Math Explainer

A result derived on screen, one step you can follow at a time.

Install it in your coding agent from its skill page: the install prompt, what it needs and the price are there.

$4.90 once, with its updates · or every skill from $9.90 a month

Good fit for

Example prompt

Use the math-director skill to make a 1-minute film proving why 1 + 2 + … + n = n(n + 1)/2.

Where should you fetch water so the walk is shortest? Try a few places, then reflect B in the river and go straight: 10 km.

A problem written for the film; every length computed and checked two ways.

The sum written forwards and backwards: every column adds to n + 1, checked with dots, then 5,050.

From OpenStax Algebra and Trigonometry 2e, 13.4.

Chalk Math

Equations and graphs that transform step by step.

Worked Problem

Try first, then the trick, every length computed, ending on the check.

Whiteboard

Drawn by hand as it is explained.