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updated version is published in Mathematical Intelligencer, Vol. 23, No. 2, pp. 17-28, Spring 2001. David W. Henderson Department of Mathematics, Cornell University, Ithaca, NY, USA, Daina Taimiða Department of Mathematics, Cornell University, For God's sake, please give it up.  Wolfgang Bolyai urging his son János Bolyai to give up work on hyperbolic geometry. In June of 1997, Daina was in a workshop watching the leader of the workshop, David, helping the participants study ideas of hyperbolic geometry using a paper and tape surface in much the same way that one can study ideas of spherical geometry by using the surface of a physical ball. But, Wait! Constructions of Hyperbolic Planes We will describe three different isometric constructions of the hyperbolic plane (or approximations to the hyperbolic plane) as surfaces in 3-space. 1. This is the paper and tape surface that David learned from William Thruston. Figure 1. 2. Figure 2. Figure 3. 3. 1.

Math Isn't Just Computation. So Why Is That All We Teach? - Education A reader named Monika Hardy recently noticed that I harp a lot on the importance of math when blogging about education. (Guilty as charged.) So, she sent me an excellent talk from the recent TEDGlobal event from this summer. The speaker is Conrad Wolfram, brother of Stephen Wolfram, the polyglot behind the applications Mathematica and Wolfram|Alpha, who runs the firm Wolfram Research. His idea: Math is made up of four parts, and our schools are only teaching one of them. The elements of math, according to Wolfram are: posing questions, translating real world problems into mathematical language, performing computation, and translating mathematical answers into real world solutions. Computers should be doing those calculations. What about the processes needed to solve mathematical problems? Check out the video, it's really good stuff—at least, I think so.

Olivia's Butterfly This is a very simple hat and very quick to make. Using a J hook and worsted weight yarn, I used red heart, and it fits a 20 1/2 inch head very nicely. Very easily adjustible by either adding increase rows or taking away. Rnd 1) ch3, 11dc in 3rd ch from hook (11dc) sl st to top of first dc (now and through out),Rnd 2) ch2, (does not count as dc now and through out) 2dc in each st around, sl st to top of first dcRnd 3) ch 2 * 2dc in first st, 1dc in next st around, repeat from * around slip st to joinRnd 4) ch2, *2dc in first st, dc in next 2dc , repeat from * around, joinRnd 5) ch2, * 2dc in first st, dc in next 3dc , repeat from * around, join Rnd 6) ch2, dc in same st and each st around Rnd 7 and 8) Repeat rnd 6 Rnd 9) ch2, dc in same st, dc in next 21 sts, ch10, skip next 9 sts, dc in next st and in each st accross, slip st to join Rnd 10) ch2, dc in same st and in next 21 sts, ch 10, skip 10 chains, dc in next dc and in each remaining dc, slip st to join Rnd 11 and 12) Repeat rnd 10

Learning to Hyperbolic Crochet - Experimental Algebra and Geometry Lab Before creating your own Hyperbolic Plane, one must first learn basic crochet skills such as:how to make a chain and how to single crochet. For additional assistance on learning how to make a chain and single crochet, click the following links for instructional videos:Starting ChainSingle Crochet. Once you learn those two crochet skills, it is time to move on to the Hyperbolic Crochet. Follow the next steps to create a the Hyperbolic Plane: Step 0. The following links provide more explanation and detail:Hyperbolic Crochet Video by the Institute for FiguringCrocheting the Hyperbolic Plane by Professors Taimina and HendersonCrochet Hyperbolic Corals by the Institute for Figuring Contact Dr. TaskRabbit: Life is busy. We can help. Patterns Everyone who has crocheted before has practiced hyperbolic crochet! When you crochet ripples, ruffles, curls and twists you are creating hyperbolic coral reef like forms. Here are some links to various free patterns to help get you started, including a knit shell pattern ( in case you prefer to knit:-) Please keep in mind that this will be a large display. Work of all sizes will be needed including large versions of whatever you want to create. I suggest using these patterns as inspiration. I can't wait to see your creations! note: Please follow any copyright requests made by designers. Basic Hyperbolic Plane pattern - beginner Basic Pseudosphere pattern - beginner Basic Crochet Pseudosphere Coral pattern - beginner Pink Anemone Oasis pattern - advanced beginner (just have to know how to follow a simple pattern) Lion Brand - Basic "How to Crochet" Instructions & video Cobblers Cabin -Chrysanthemum - a basic coral form Lion Brand Kelp Patterns: one, two, three, four, five, and six Sea Mouse

StumbleUpon WigUsing straight needles or one set of circulars, cast on 96 sts. Work in 2 x 2 rib until the piece is as long as the distance between the bottom of your chin, and your eyebrow (about 6.5"), ending with a WS row. NOTE: The extra stitches along the edge of the work will balance the width of the first and last ribs. Later on, when the bangs are added, these stitches will become parts of purl ribs. If more length in the main body of the wig is desired, work more rows at this point. Bangs With RS facing and using backward loop cast on, loosely CO 32 sts. If more length in the bangs is desired, work more rows at this point. Work Decreases Using diagram B below as a guide, rearrange stitches on needles and add stitch markers. NOTE: Decreases will be worked identically at the front and back of the wig. Begin decrease round by working decreases over bangs.

Free Hobbes Crochet Pattern I've finally decided to write up my Hobbes pattern and instead of selling it I'd like to give it to you for free. The reason he is free is because the creator of Calvin and Hobbes, Bill Watterson did not want to commercialize his work so keeping that in mind Please don't sell this pattern and don't sell the completed work. ~~~~~~~~~~~~~~~~~~~~ I originally made this up for my son because of his love for Hobbes (he's 23 now) I armed myself with Watterson's brilliant drawings as a reference. I made this pattern to look as close as possible to the Hobbes' drawings . I realized that Hobbes could be broken down into basic shapes. He also had the muzzle of a cat so I looked to the famous Amineko cat. Once I got the shapes down I worked on size. Until I started making him I never realized how different Hobbes looks from a regular cat. His head and body are a lot longer thanan normal cat plus he has the shortest fattest legs. That caused me problems since tubular legs and arms don't want to bend. Resources: