Geometry

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• Kids and Teens: Science and Math: Math: Geometry 

• Area and Volume Formulas  - Includes basic formulas for common geometrical figures.
• Bob's Pages  - An interactive presentation of different geometric figures, including polyhedra, fractals, the arbelos, logarithmic spiral and Soddy's Hexlet.
• The Complete Quadrilateral  - An interactive column by Alex Bohomolny, discussing theorems and presenting illustrative demonstrations through java-enabled applets.
• Cubical Box Distances  - Uses java-enabled applets to determine distances. Also provides problems and calculations on surface distances on a cuboid.
• Diamond Theory  - Description of new geometric theory, which reveals that Euclidean symmetry may be invariant under rather interesting groups of noncontinuous (and asymmetric) transformations.
• Encyclopedia of Triangle Centers  - A compendium of more than 1,000 triangle centers. Also includes links related to triangle centers.
• Erich's Packing Center  - Illustrated solutions to several covering, packing, and tiling problems. Includes some animated demonstrations.
• Geo Doubek  - Applet that draws Lissajous Figures.
• Geometry Activities  - Filled with problem-solving modules for simplified geometry.
• Geometry and the Imagination in Minneapolis  - A collection of handouts during a two-week summer workshop held at the Geometry Center, from June 17-28, 1991.
• The Geometry Center  - A unified mathematics computing environment supporting math and computer science research, mathematical visualization, software development, application development, video animation production, and K-16 math education.
• Geometry Formulas and Facts  - Presents a document excerpted from the CRC Standard Mathematical Tables and Formulas (30th edition, 1995). Excerpt does not cover differential geometry.
• Geometry in Action  - Page collects various areas in which ideas from discrete and computational geometry (meaning mainly low-dimensional Euclidean geometry) meet some real world applications.
• The Geometry Junkyard  - A collection of geometry materials such as usenet clippings, web pointers, excerpts, papers, abstracts, programs and other materials that are entirely mathematical in nature.
• Geometry Page of the Interactive Mathematics Miscellany and Puzzles  - Includes various geometry topics, some accompanied by Java-enabled applets, for teachers who want to enliven their web pages or classroom presentation.
• Hyperbolic Geometry Using Cabri  - Includes macros for illustrating non-Euclidean geometry in the Poincare disc model.
• The Kepler Conjecture  - Provides historical accounts, proofs, academic papers and other information on the packing of spheres.
• The Lepidoptera of the Circles  - Uses java-enabled applets to illustrate and prove the butterfly theorem.
• The Math Forum: Geometry Research  - Serves as a venue for academics to post research announcements, seminars, reviews and abstracts of papers. Also allows for the discussion of academic papers.
• Mathematical Curves and Surfaces  - A gallery of computer-generated mathematical forms using explicit, parametric, polar, cylindrical or spherical coordinates. Available in French and English.
• Mow's Cabri II  - Collection of geometry data for Cabri Geometry II.
• Native American Geometry  - Provides an in-depth look at ancient geometry which originates from a simple circle. Traces the history of the geometry that led to modern cultural symbols.
• Packomania  - Packings of objects in containers, including circles in a square, circles in a circle, or circles in rectangles. With downloadable source files.
• Peek  - Program for N-dimensional polytope visualization.
• Steiner Surfaces  - Discussion of the geometry of J. Steiner's images of the real projective plane. Includes POV codes for graphics and animation.
• Visual Dictionary of Famous Plane Curves  - Provides information, history, illustration of common geometric curves. Also includes methods of classifying curves.
• Wallpaper Groups  - Provides illustrations and information on different plane symmetry groups.
• Wilson's Inversive Geometry  - Proving theorems using the Klein viewpoint and some CabriJava illustrations.
• Xah Lee's Home Page  - Includes a visual dictionary of famous plane curves, illustration of common surfaces, information on discontinuous groups of rotation and translation in the plane, and projective geometry.