Math

Thanks to Umesh for the suggestion! If the large circle has a radius equal to 1, what is the radius of each small circle? Subscribe: https://www.youtube.com/user/MindYourDecisions?sub_confirmation=1 Send me suggestions by email (address at end of many videos). I may not reply but I do consider all ideas! If you buy from the links below I
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Happy Pi Day! At 3/14/15 at 9:26 the time will be accurate to pi for 7 decimal places. What’s your favorite fact about pi? Links to proofs and more below in the description. 1. The definition 00:10 Related: the area of circle intuitive explanation 2. Pi is irrational 00:47 Proof (video) Proof (blog post) Proving
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I bet this one will give many adults a good challenge too. Thanks to Pett for the suggestion! Special thanks this month to: Kyle, Mike Robertson, Michael Anvari, Daniel Lewis, Robert Zarnke. Thanks to all supporters on Patreon! http://www.patreon.com/mindyourdecisions Singapore International Math Olympiad Challenge (SIMOC) 2015 – Primary 5 Paper, problem 24. Sample Papers Subscribe:
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We’re exploring the world of Chicken Nuggets and Frobenius numbers. 43 has long been a special number in the world of McNugget mathematics, but 11 is also important! More links & stuff in full description below ↓↓↓ This video features Dr James Grime. NUMBERPHILE Website: http://www.numberphile.com/ Numberphile on Facebook: http://www.facebook.com/numberphile Numberphile tweets: https://twitter.com/numberphile Subscribe: http://bit.ly/Numberphile_Sub
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How do you measure the length of a spiral on a cylinder? There is a neat trick! If you like my videos, you can support me at Patreon: http://www.patreon.com/mindyourdecisions Connect on social media. I update each site when I have a new video or blog post, so you can follow me on whichever method is
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Featuring Grant Sanderson, creator of 3blue1brown. Extra footage from this interview: https://youtu.be/pJyKM-7IgAU 3blue1brown video on the shadow a cube: https://youtu.be/ltLUadnCyi0 More links & stuff in full description below ↓↓↓ 3blue1brown: https://www.youtube.com/channel/UCYO_jab_esuFRV4b17AJtAw Grant on The Numberphile Podcast: https://youtu.be/A0RH93XvSyU Numberphile is supported by the Mathematical Sciences Research Institute (MSRI): http://bit.ly/MSRINumberphile We are also supported by Science Sandbox,
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Catch a more in-depth interview with Ben Sparks on our Numberphile Podcast: https://youtu.be/-tGni9ObJWk Check out Brilliant (and get 20% off) by clicking https://brilliant.org/numberphile More links & stuff in full description below ↓↓↓ Golden seeds limited edition T-Shirt: https://teespring.com/NP-Seeds More Golden Ratio stuff: http://bit.ly/Golden_Ratio More Ben Sparks Numberphile videos: http://bit.ly/Sparks_Playlist Ben’s Twitter: https://twitter.com/SparksMaths Ben’s website: www.bensparks.co.uk
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Featuring Neil Sloane. Visit https://gift.climeworks.com/numberphile to give the gift of CO₂ removal. Use code NUMBERPHILE10 for 10% off your purchase in December (sponsor) More links & stuff in full description below ↓↓↓ Neil Sloane is the founder of The OEIS: https://oeis.org More videos with Neil: http://bit.ly/Sloane_Numberphile Prime Playlist: https://bit.ly/PrimePlaylist Note the 17350-digit prime we feature
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The Monster Group explained. Conway playlist: http://bit.ly/ConwayNumberphile More links & stuff in full description below ↓↓↓ Featuring John Conway (Princeton University) and Tim Burness (University of Bristol). Brown papers and Numberphile artwork: http://bit.ly/brownpapers More Conway on this topic: http://youtu.be/xOCe5HUObD4 And Conway on Game of Life, etc: http://bit.ly/JohnConway A little extra bit from Tim: http://youtu.be/MXKiih4JJvQ Support
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This is a nice little logic puzzle from Terry Stickels! Books by Terry Stickels (including “Contemporary Brainteasers”) http://www.terrystickels.com/books.html Subscribe: https://www.youtube.com/user/MindYourDecisions?sub_confirmation=1 Send me suggestions by email (address in video). I consider all ideas though can’t always reply! Like many YouTubers I use popular software to prepare my videos. You can search for animation software tutorials on
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Recently Russia’s Prime Minister Mikhail Mishustin visited 11th grade students (about 17-18 years old) and asked them a challenging geometry problem. Can you figure it out? I came across this puzzle in Alex Bellos’s column on The Guardian. He has a new book that I wanted to share titled “The Language Lover’s Puzzle Book.” I
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Can you pass this logic test that stumps many people? References https://brilliant.org/problems/the-boxes/ http://www.dailymail.co.uk/femail/food/article-3905480/Are-smart-solve-beer-burger-brainteaser-Tricky-maths-puzzle-sweeping-web-harder-looks.html Subscribe: https://www.youtube.com/user/MindYourDecisions?sub_confirmation=1 Send me suggestions by email (address in video). I consider all ideas though can’t always reply! Like many YouTubers I use popular software to prepare my videos. You can search for animation software tutorials on YouTube to learn how to
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If a semicircle and its flipped copy are placed side by side, how much distance do they span from end to end? This is a neat problem adapted from a Mathematical Olympiad Qualifying Test in the Philippines. Can you figure it out? Subscribe: https://www.youtube.com/user/MindYourDecisions?sub_confirmation=1 Send me suggestions by email (address at end of many videos).
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Matt Parker talks about numbers – as he often does. His book “Humble Pi” is at: http://bit.ly/Humble_Pi More links & stuff in full description below ↓↓↓ The book on Amazon: https://amzn.to/2NKposg Numberphile podcast is on your podcast player. Or the website is: https://www.numberphile.com/podcast And it’s on YouTube too: http://bit.ly/Numberphile_Pod_Playlist The Knight’s Tour T-Shirt is in
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Featuring Hannah Fry discusses Train Graphs. More links & stuff in full description below ↓↓↓ Hannah’s website, including links to her many and varied projects… and latest books: https://hannahfry.co.uk Her latest book (with Adam Rutherford) is the Complete Guide to Absolutely Everything (Abridged): https://amzn.to/30Mr6UE Hannah on Numberphile: http://bit.ly/hannah_vids Hannah on the Numberphile podcast: https://youtu.be/KKCjQWmUwv8 Numberphile
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Thanks to Jumar for the suggestion! Can you solve this interesting geometry problem? 0:00 Problem 1:10 Similar triangles 2:29 Solution Subscribe: https://www.youtube.com/user/MindYourDecisions?sub_confirmation=1 Send me suggestions by email (address at end of many videos). I may not reply but I do consider all ideas! If you buy from the links below I may receive a commission
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Professor Tony Padilla is back with another epic number. Our Big Number playlist of previous videos: http://bit.ly/Big_Numbers More links & stuff in full description below ↓↓↓ Busy Beavers on Computerphile: https://youtu.be/CE8UhcyJS0I With thanks to Agustín Rayo himself. Read more from Prof Rayo at: http://web.mit.edu/arayo/www/bignums.html And see his website at: https://arayo.scripts.mit.edu/home/ Tony Padilla: https://twitter.com/DrTonyPadilla Numberphile is
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Tadashi is back, this time looking at drooping paper (and toilet paper). More links & stuff in full description below ↓↓↓ Subscribe to Numberphile and never miss a floppy paper video: http://bit.ly/Numberphile_Sub Playlist of Tadashi Tokieda videos: http://bit.ly/tadashi_vids Pizza and Gaussian curvature: https://youtu.be/gi-TBlh44gY Support us on Patreon: http://www.patreon.com/numberphile NUMBERPHILE Website: http://www.numberphile.com/ Numberphile on Facebook: http://www.facebook.com/numberphile
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Check our sponsor The Great Courses Plus (free trial): http://ow.ly/j5cB30hIvm2 This video features Cliff Stoll. More links & stuff in full description below ↓↓↓ More Cliff Stoll videos: http://bit.ly/Cliff_Videos Buy a Klein Bottle from Cliff – it’s an experience: http://www.kleinbottle.com Discuss this video on Brady’s subreddit: https://redd.it/96x6c4 Numberphile is supported by the Mathematical Sciences Research
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The abc Conjecture may have been proven by a Japanese mathematician – but what is it? More links & stuff in full description below ↓↓↓ Feeling brave and want to read the papers by Shinichi Mochizuki – http://www.kurims.kyoto-u.ac.jp/~motizuki/papers-english.html (scroll to the bottom) This video features Dr James Grime who tweets at https://twitter.com/jamesgrime NUMBERPHILE Website: http://www.numberphile.com/
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Albert Einstein was challenged with a simple riddle in a 1934 correspondence with the psychologist Max Wertheimer. Can you figure it out? Thanks to all patrons! Special thanks to: Shrihari Puranik, Richard Ohnemus, Michael Anvari, Kyle. We are the only channel to feature math topics suggested by people around the world. Support on Patreon to
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Fields Medallist and math “celebrity” Cédric Villani is famous for wearing ornate spiders on his lapel. More Villani videos: http://bit.ly/Villani_Videos Cédric Villani website: http://cedricvillani.org His book Birth of a Theorem (Amazon): http://bit.ly/BirthOfATheorem Villani talks about his Fields Medal: https://youtu.be/Vp3sgYKULp0 Numberphile is supported by the Mathematical Sciences Research Institute (MSRI): http://bit.ly/MSRINumberphile We are also supported by
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Featuring Professor Howard Masur from the University of Chicago. Filmed at the Mathematical Sciences Research Institute (MSRI). Part 2 of this interview: https://youtu.be/AGX0cLbHaog Patreon: http://www.patreon.com/numberphile Numberphile is supported by the Mathematical Sciences Research Institute (MSRI): http://bit.ly/MSRINumberphile We are also supported by Science Sandbox, a Simons Foundation initiative dedicated to engaging everyone with the process of
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The famed Poincaré Conjecture – the only Millennium Problem cracked thus far. More links & stuff in full description below ↓↓↓ Ricci Flow (used to solve the problem): http://youtu.be/hwOCqA9Xw6A Riemann Hypothesis: http://youtu.be/d6c6uIyieoo Extra interview footage with Jim Isenberg: http://youtu.be/7eJleW0JcKg Grigori Perelman’s paper: http://bit.ly/perelmanpaper Discussed here by Katie Steckles and James Isenberg. Support us on Patreon:
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People around the world have asked me this and similar problems. Learn how to solve using only geometry (and a little bit of algebra). There are many other ways to solve the problem too https://www.mathalino.com/reviewer/plane-geometry/02-area-common-arcs-quarter-circles Subscribe: https://www.youtube.com/user/MindYourDecisions?sub_confirmation=1 Send me suggestions by email (address in video). I consider all ideas though can’t always reply! Like many
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This problem is adapted from an Oxford University admissions question. They say if you can solve this in your head, you are a genius 😉 Alex Bellos’s column on The Guardian https://www.theguardian.com/science/2021/jul/12/did-you-solve-it-oxford-university-admissions-questions Subscribe: https://www.youtube.com/user/MindYourDecisions?sub_confirmation=1 Send me suggestions by email (address at end of many videos). I may not reply but I do consider all ideas!
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Tadashi Tokieda puts $20 on the line… More links & stuff in full description below ↓↓↓ More Tadashi videos: http://bit.ly/tadashi_vids Paperclips: https://youtu.be/wGkvyN6s9cY Video by Brady Haran and Pete McPartlan (animations by Pete) Support us on Patreon: http://www.patreon.com/numberphile NUMBERPHILE Website: http://www.numberphile.com/ Numberphile on Facebook: http://www.facebook.com/numberphile Numberphile tweets: https://twitter.com/numberphile Subscribe: http://bit.ly/Numberphile_Sub Numberphile is supported by the Mathematical
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Three squares are placed in a row. Connect the bottom left corner of each square to the top right corner of the third square, forming angles with measures a, b, c with the horizontal. What is the sum of a, b, and c? Many people requested this problem, and I thank Roberto O. and Cardist
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Johnny Ball on Russian and Egyptian Multiplication. Check out Brilliant (get 20% off their premium service): https://brilliant.org/numberphile (sponsor) More links & stuff in full description below ↓↓↓ More on Johnny Ball, including his books and live shows: https://www.johnnyball.co.uk Russian multiplication is also known as Ethiopian multiplication. Why Use Binary? (on Computerphile) – https://youtu.be/thrx3SBEpL8 Discuss on
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An exciting paper about gaps between prime numbers – a step closer to proving the twin prime conjecture. More links & stuff in full description below ↓↓↓ Extra footage at http://youtu.be/D4_sNKoO-RA The proof was published by Yitang “Tom” Zhang from the University of New Hampshire. We’re discussing it in simple terms with Numberphile regulars –
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Students in the UK faced a similar question to this one. Don’t give up–U can solve it! Adapted from [GCSE Edexcel Further Math] How would you solve for x? from HomeworkHelp Subscribe: https://www.youtube.com/user/MindYourDecisions?sub_confirmation=1 Send me suggestions by email (address at end of many videos). I may not reply but I do consider all ideas! If
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Archimedes’s famous Cattle Problem had a truly epic solution. Featuring Alex Bellos. More links & stuff in full description below ↓↓↓ Alex Bellos: http://www.alexbellos.com More Alex videos on Numberphile: http://bit.ly/Bellos_Playlist So You Think You’ve Got Problems by Alex Bellos Amazon: https://amzn.to/2KR9Get Signed copies via MathsGear:http://bit.ly/BellosProblemsSigned More Alex books: https://amzn.to/2KQTc5Y The Cattle Problem by AH Bell:
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I received many requests for this challenging problem. Can you solve it? Thanks to Toli for the suggestion! Geometry solution in method 1 http://128.192.17.191/EMT668/EMAT6680.F99/Estes/15degrees/15degreesgeometric.html Another geometry solution http://128.192.17.191/EMT668/EMAT6680.F99/Estes/15degrees/solution2.html Trigonometry solution http://128.192.17.191/EMT668/EMAT6680.F99/Estes/15degrees/15degreestrigonometric.html Go Geometry discussion https://gogeometry.blogspot.com/2009/11/problem-395-square-15-degree.html https://drive.google.com/file/d/1A0Az5nJ9wGBwcM2F4gQY2dSfeKJZ1gSS/view Subscribe: https://www.youtube.com/user/MindYourDecisions?sub_confirmation=1 Send me suggestions by email (address at end of many videos). I may not reply but I
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A chat about some of the ways legendary physicist Richard Feynman cracked safes (filing cabinets) at Los Alamos during the Manhattan Project. More links & stuff in full description below ↓↓↓ Discussed by Professor Roger Bowley. My Favourite Scientist on Feynman: http://www.youtube.com/watch?v=qoYWfytx5QA Feynman Diagrams: http://www.youtube.com/watch?v=3bbJeMBHq0g Enigma: http://www.youtube.com/watch?v=G2_Q9FoD-oQ NUMBERPHILE Website: http://www.numberphile.com/ Numberphile on Facebook: http://www.facebook.com/numberphile Numberphile
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A triangle with sides of 4, 3, and 5 is drawn inside a square as shown. What is the length of the square’s side? It’s a fun little geometry problem! Sources https://www.instagram.com/p/Btw9ZfyBz5w/ http://mathhelpforum.com/geometry/236852-area-square-right-triangle-inside.html Egyptian Proverb http://oaks.nvg.org/egyptian-proverbs.html Subscribe: https://www.youtube.com/user/MindYourDecisions?sub_confirmation=1 Send me suggestions by email (address in video). I consider all ideas though can’t always reply! Why
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This was asked to students in 1801, but it is still a challenging and fun problem to solve to this day! Source See page 5, problem 24 https://archive.org/details/cambridgeproblem00cambuoft/page/4/mode/2up Subscribe: https://www.youtube.com/user/MindYourDecisions?sub_confirmation=1 Send me suggestions by email (address at end of many videos). I may not reply but I do consider all ideas! If you buy from
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This video features Dr Hannah Fry (more links below) ↓↓↓ Check out Brilliant.org: https://brilliant.org/numberphile (20% off premium subscription) That circle cutting problem on Brilliant: https://brilliant.org/NumberphileSandwich Hannah Fry on Twitter: https://twitter.com/FryRsquared Read about Hannah’s Xmas book (and buy a copy to show her some support!): http://www.bradyharanblog.com/blog/hannahs-book More Hannah videos on Numberphile: http://bit.ly/hannah_vids Animation by Pete McPartlan
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Happy #PiDay! When two of the hardest tests in the world cover the same problem, you know it’s a big deal. References Wikipedia article https://en.wikipedia.org/wiki/Proof_that_22/7_exceeds_%CF%80 Putnam exam 1968 A1 https://prase.cz/kalva/putnam/putn68.html JEE Advanced 2010 Paper Solutions Part-1 | IIT-JEE | Strategy, Tips, & Tricks | Paper Discussion (see around 55:30) https://youtu.be/Zz4buu5y7_8?t=3330 Proving 22/7 is greater than
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