Geometry & Trigonometry
Shapes, angles and trig functions.
Geometry
How the Pythagorean Theorem Works, with Proofs and Examples
See why a squared plus b squared equals c squared for right triangles, with a clear area proof, common triples, and practical examples.
GeometryHow Sine, Cosine and Tangent Work in Right Triangles
Learn sine, cosine and tangent as ratios of triangle sides, see the exact values for common angles, and understand how they extend to the unit circle.