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Stay Curious Black / M
$20.00
There are three types of color receptors in your eye: red, green and blue. But how do we see the amazing kaleidoscope of other colors that make up our world? Watch the lesson for the answer. Meanwhile, stay curious! View Full Lesson/Credits • Eco-friendly, high-quality, minimal waste• Unisex • 100% ring-spun cotton (heather colors contain polyester) • Baby-knit jersey • Shoulder-to-shoulder taping • Cover stitched and hemmed sleeves • Side-seamed
Left hand, best hand Heather Midnight Navy / M
$20.00
Today, about one-tenth of the world’s population are southpaws. Why are such a small proportion of people left-handed -- and why does the trait exist in the first place? Daniel M. Abrams investigates how the uneven ratio of lefties and righties gives insight into a balance between competitive and cooperative pressures on human evolution. View Full Lesson/Credits • Eco-friendly, high-quality, minimal waste • Unisex • 100% ring-spun cotton (heather colors contain polyester) • Baby-knit jersey • Shoulder-to-shoulder taping • Cover stitched and hemmed sleeves • Side-seamed
Oh Beehive! Heather True Royal / M
$20.00
Honeybees are some of nature's finest mathematicians. Not only can they calculate angles and comprehend the roundness of the Earth, these smart insects build and live in one of the most mathematically efficient architectural designs around: the beehive. View Full Lesson/Credits • Eco-friendly, high-quality, minimal waste• Unisex • 100% ring-spun cotton (heather colors contain polyester) • Baby-knit jersey • Shoulder-to-shoulder taping • Cover stitched and hemmed sleeves • Side-seamed
TED-Ed Loves You Tote Cream
$20.00
Purchase a TED-Ed Loves You tote bag and you'll be helping TED-Ed share high-quality educational content with the world for free! Your messages of encouragement, and the stories you share about how you use TED-Ed animations and programs bolster our work and give us a glimpse of the impact we hope to have on the world. TED-Ed loves you, ju, dich, ty, tebe...all of you! You show us your , and we you back.• 100% certified organic cotton 3/1 twill• Dimensions: 16” x 14½” x 5”• Weight limit: 30lbs (13.6 kg)• Open main compartment
TED-Ed Loves You Tote Black
$20.00
Purchase a TED-Ed Loves You tote bag and you'll be helping TED-Ed share high-quality educational content with the world for free! Your messages of encouragement, and the stories you share about how you use TED-Ed animations and programs bolster our work and give us a glimpse of the impact we hope to have on the world. TED-Ed loves you, ju, dich, ty, tebe...all of you! You show us your , and we you back.• 100% certified organic cotton 3/1 twill• Dimensions: 16” x 14½” x 5”• Weight limit: 30lbs (13.6 kg)• Open main compartment
Stay Curious Notebook
$15.00
Use this notebook for class notes, doodling, or jotting down your big (or small) ideas. Or add it to your ever-growing pile of too-nice-to-use journals.• Covers with soft-touch coating• Cover weight: 10.38 oz/yd² (352 g/m²)• Page weight: 2.62 oz/yd² (89 g/m²)• Metal wire-o binding• 140 dotted pages• Size: 5.25′′ × 8.25′′ (13 × 21 cm)• Blank product sourced from the US
How many ways are there to prove the Pythagorean theorem? - Betty Fei
96KLikes
3,821,367Views
2017Sep 11
Check out our Patreon page:   / teded   View full lesson: https://ed.ted.com/lessons/how-many-w... What do Euclid, 12-year-old Einstein, and American President James Garfield have in common? They all came up with elegant proofs for the famous Pythagorean theorem, one of the most fundamental rules of geometry and the basis for practical applications like constructing stable buildings and triangulating GPS coordinates. Betty Fei details these three famous proofs. Lesson by Betty Fei, directed by Nick Hilditch. Thank you so much to our patrons for your support! Without you this video would not be possible. Steph, Jack Ta, Jose Fernandez-Calvo, PnDAA , Marcel Trompeter-Petrovic, Radoslava Vasileva, Sandra Tersluisen, Fabian Amels, Sammie Goh, Mattia Veltri, Quentin Le Menez, Sarabeth Knobel, Yuh Saito, Joris Debonnet, Martin Lõhmus, Patrick leaming, Heather Slater, Muhamad Saiful Hakimi bin Daud, Dr Luca Carpinelli, Janie Jackson, Jeff Hanevich, Christophe Dessalles, Arturo De Leon, Delene McCoy, Eduardo Briceño, Bill Feaver, Ricardo Paredes, Joshua Downing, Jonathan Reshef, David Douglass, Grant Albert, Paul Coupe.

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TED-Ed

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