Whistler Alley Mathematics

These are some mathematics investigations I have pursued over the years. They may be of some interest to teachers, students, or hobbyists. I try to convey a conceptual understanding, usually without rigorous proof. Some of the lessons are accompanied by questions and suggestions for extensions.

Zapato DC de 19925 skate DC B01AYB5HYS Mujer Trase V SE rojo c205ecb




Cuero
Importado
Goma único
Eje mide aproximadamente parte baja del arco
Vulcanizado construcción
Resistente a la abrasión suela de goma adhesiva
Some of the lessons are accompanied by questions and suggestions for extensions.

In my pursuit of a teaching career, I was told to justify the study of each concept by establishing its relevance to the students’ lives. Sorry, but I still have trouble buying into that one. Fortunately, poetry and music are rarely put to that same test. As I glance at the list below, I must concede that it would be difficult to convert any of the lessons into food, shelter, or money. These are things that interested me, and now I understand them better. If there is a reward, it is the fact that every time I do this I get better at figuring things out.

I occasionally get email from people seeking permission to use my work. Feel free to cite, quote, edit, reproduce, or distribute anything on this site. Do not worry about putting my name on it, but please do not put your own name on it.

Many of these presentations use the Geometer’s Sketchpad, but only one of them actually requires it. If you do not have the software, let me suggest that you follow this link to Key Curriculum Press and look into it.

Paul Kunkel


Zapato DC de 19925 skate DC B01AYB5HYS Mujer Trase V SE rojo c205ecb - movie-store.online

Recent Changes

March 16, 2016

Updated the animations on Hanging With Galileo.

October 23, 2015

Updated the animations on Reuleaux Triangle.

October 9, 2015

Updated the animations on the Vernier Scale page of the Geometry of Surveying.

October 8, 2015

Zapato DC de 19925 skate DC B01AYB5HYS Mujer Trase V SE rojo c205ecb

Updated the animations on Linkages.

October 4, 2015

Updated the animations on On the Square.

September 25, 2015

Updated the animations on Tangent Circles.

September 23, 2015

Updated the lead page of Conic Sections and Construction.
The page it replaced had java animations that were not being treated well by modern browsers. New images were generated with the developmental Web Sketchpad, which is producing very satisfying results. This appears to be the future, so expect more of my pages to be similarly updated soon.

February 26, 2015

Added Book VII to the Conics of Apollonius.
This is the final surviving book of the treatise.

October 22, 2014

Added Book VI to the Conics of Apollonius.

June 10, 2014

Added Book V to the Conics of Apollonius.


 Includes GSP-3 files

 Includes GSP-4 files

 Includes GSP-5 files Contents:

The Brachistochrone

We are given two fixed points in a vertical plane. A particle starts from rest at one of the points and travels to the other under its own weight. Find the path that the particle must follow in order to reach its destination in the briefest time.

This is a famous problem in the calculus of variations. Nothing new is presented here, but the explanation is more thorough than most.


Buffon’s Needle

An old probability exercise is aided by an interactive Sketchpad file. By manipulating the sketch, an intuitive understanding may be gained, even if the student has had no introduction to calculus.


Zapato DC de 19925 skate DC B01AYB5HYS Mujer Trase V SE rojo c205ecb

Chinese Handcuffs This has no lesson, only questions. It is just an interesting animated file, which invites student investigation. It has applications for geometry,

Zapatillas Vans Old Skool de Cuero VN0A38G1QD5 Gris (Cuero) Oxford / Drizzle Grey Vans Unisex Old Skool Zapatillas clásicas de skate rojo Zapatillas DC Mujeres Chelsea TX SE Sneaker Chambray Clásicos de base Slip-on (Tm) para hombres de Vans Tablero de ajedrez negro sin blanco Supra Vaider LC Sneaker Negro Negro , Vans Auténtico Horizonte abstracto , Vans Unisex Old Skool Zapatillas clásicas de skate San Francisco / Giants / Black , Lakai Limited Footwear Mens Griffin Textil gris / negro , Vans Unisex Old Skool Zapatillas clásicas de skate (Reverso Floral) Blk / Trwht Vans Unisex Era Zapatillas de skate, clásicas Low-Top cordones Estilo en Durable Doble costura Lienzo y Original Suela de gofre Azul / gris / rojo , Clásicos de base Slip-on (Tm) para hombres de Vans Tablero de ajedrez negro sin blanco Vans Unisex Old Skool Zapatillas clásicas de skate Hierro marrón / blanco verdadero , Vans Old Skool Unisex Adults Low-Top Trainers Cabernet / True White , Vans Sk8-Hi Unisex Top informal Zapatos de skate, cómodos y duradero en Waffle de la firma Suela de goma (Mte) Negro / Cuero , Vans Unisex Old Skool Zapatillas clásicas de skate Negro / Wasabi , Zapatillas DC Beach Trase TX Skate Agua , Vans Unisex Old Skool Zapatillas clásicas de skate Mahogany Rose True White , Supra Vaider LC Sneaker Medianoche blanco Zapato de skate DC Wnt Spartan High WC para mujer Negro / armadura , Supra Mujer / Hombre Noiz Sneaker Tiza malva / tiza malva , Vans Old Skool Unisex Adults Low-Top Trainers (Mix Checker) Negro / Blanco verdadero , Supra Vaider LC Sneaker Amber Gold / White , Vans Herren Authentic Core Classic Sneakers Blanco / apagado blanco , Vans Unisex Old Skool Zapatillas clásicas de skate Very Berry True White , Clásicos de base Slip-on (Tm) para hombres de Vans Tablero de ajedrez negro / de peltre Vans Auténtico Suela negra Harbour Gray , Supra Vaider Skate Shoe Negro / Blanco-blanco / Negro Zapatillas de skate Vans Unisex Old Skool Silver Lining / True White Vans Unisex Old Skool Zapatillas clásicas de skate negro rojo
trigonometry, and probability. Fair warning: The discussion revolves about a figure that appears only when the sketch is animated. Without Geometer’s Sketchpad, this one will make little sense at all.


Conic Sections and Construction

My emphasis is on geometric properties of the conic sections, particulary understanding that has been handed down to us in ancient texts. There also are some challenging constructions.


The Geometry of Surveying

This used to be my job, and I enjoyed studying all of the geometrical concepts that were part of the science of land surveying. In this article I discuss the instruments of the profession, their operating principles, their error, and their calibration.


Hanging with Galileo

An investigation into the catenary, the curve formed by a chain suspended at both ends. It also extends into the curve of the main cables on a suspension bridge, which, interestingly, is not a catenary.


Inversion Geometry Sandalia Hurvane XLT de Teva para mujer, Hazel Black, 9 US Lago Black / Gray , Sandalias Bali KEEN para mujer Negro / Imán Saucony Women s Ride 10 zapatillas para correr Blanco azul , Sandalia UEek Flat-W de mujer KEEN Cuervo azul Sandalia Drew Angela para mujer Dusty Multi Metallic , Converse Chuck Taylor All Star Seasonal Color Hola Monocromo negro , Zapatillas para trail running Mutant Backcountry de La Sportiva para mujer Plum / Applegreen , NAOT Kayla Elegant Sandalias de mujer Charol negro , Under Armour Women s HOVR Sonic NC Blanco (108) / Ghost Grey adidas outdoor para mujer Terrex Swift R2 GTX Negro / Negro / Negro Calzado de running New Balance para mujer Vazee 2090 Silver Mink / Outerspace , Hush Puppies Power Walker Sneaker para mujer Blanco Sandalia del Atlas Bayton para mujer Mostaza Kenneth Cole New York - Sandalia de tiras de tobillo plano Jinny, para mujer Plata VANELi Womens Jaicee Ante negro / elástico negro , Zapatillas Sneachers Sport Women s Microburst Supersonic Fashion Sneaker Blanco negro Entrenador Ryile Hailee Cross para mujeres Gris / rosa / azul Zapatillas para mujer Del Rey TOMS Lámina natural Bobcat / Gold , Clásicos de base Slip-on (Tm) para hombres de Vans Tablero de ajedrez negro sin blanco , Sandalias de mujer Amalia de Donald J Pliner Negro Birkenstock - Sandalias de gamuza con aplicaciones de suela suave Arizona para mujer Terciopelo gris terciopelo suave plantilla , Sandalia para mujer Layne Slide de Pour La Victoire Negro Zapatillas de deporte de lona planas de corte plano Casual Superga 2790 para mujer Negro El té verde de Daniel Green Teagan Azul marino Pantuflas de lana Giesswein Neritz Antracita Aigle Parcours 2 Iso Noir , Bota de combate Myra Lug para mujer FRYE Forest Soft Oiled Suede , Shellys London Womens Terrence Camo Bota de combate Veronica para mujer FRYE Forest Soft Oiled Suede , TOMS - Suela de lino de lino clásica, cómoda y de ajuste fácil para mujer Negro sobre negro ,

If you have never studied inversion geometry, you can start here. The elementary concepts are explained. This page is a quick reference for the other lessons that employ inversion geometry.


Linkages

Draw a line segment. Did you use a straightedge? How do you know it was straight?

Java simulations are used to investigate a nineteenth century mechanics problem.


On the Square

The challenge: Given four arbitrary, unique points, A, B, C, and D, construct one line through each point such that the four lines form a square.


Orthocenter What is so significant about the orthocenter of a triangle? Why does it even have a name? This investigation was prepared for a geometry teachers’ workshop. It includes a lesson handout in Word format. This lesson was written for use in a computer lab with the Geometer’s Sketchpad, but with a little editing it should work just as well with Cabri or Cinderella.
The Planimeter

A planimeter is a drafting instrument used to measure area. Its mechanism is quite simple, but understanding why it works is more elusive.


Platonic Solids

Find the inradius, circumradius, dihedral angle, surface area, and volume of all of the Platonic solids. There is also some information about some of their other interesting properties.


Reuleaux Triangle

It is not a circle, but it has constant width. Study the properties of this figure with interactive animated sketches.


Rungs and Vineyards

How is that for a descriptive title? Here are investigations of two interesting visual effects seen from a moving automobile. It includes two interactive perspective drawings, and a discussion of the cylindrical and planar projections used to create them.


The Sliding Triangle

An interesting accidental discovery – Investigate ellipses by tracing triangle transformations.


Table Patterns

Explore geometric patterns formed in a table of modular multiplication. This one requires some elementary knowledge of congruence classes and modular arithmetic.

Zapato DC de 19925 skate DC B01AYB5HYS Mujer Trase V SE rojo c205ecb - movie-store.online


Tangent Circles

Three circles are given. How many circles can be constructed tangent to all three? How are they constructed? This lesson includes ten animations covering all of the special cases. Some of them are very complex. A little knowledge of circle inversions would help.


Volume of a Torus Do you already know the volume of a torus? Then humor me. I just figured Zapato DC de 19925 skate DC B01AYB5HYS Mujer Trase V SE rojo c205ecb it out, and I got a chance to try out this new graphics software.


Resources


The Geometer’s Sketchpad Workshop

It is plain to see that I am very fond of Sketchpad. This page was created after the release of version 4. The idea is to have a place to exchange ideas with other users, especially those who are using the advanced features. Here are some custom tools and some information on Java Sketchpad.

Skateboarding
Sketchpad Gallery These are some of my best sketches. You may find them useful or interesting by themselves.

Geometry Construction Reference

Thirteen elementary straightedge 2074809
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and compass constructions are described and illustrated. The original version, in Word format, can be downloaded and distributed.

Back to Whistler Alley


Last update: March 16, 2016 ... Paul Kunkel whistling@whistleralley.com
For email to reach me, the word geometry must appear in the body of the message.