Mathematical Visual ProofsI often get requests to give a visual proof of the claim that 1+2+3+4+5+... = -1/12 that is, that the sum of all positive integers is -1/12. One problem with this is that it isn't true using the techniques of real analysis, so visualizing it can be challenging (not to mention that visualizing negative numbers is challenging in and of itself). Another challenge is that people get pretty angry with the various methods used to produce this claim.
However, we are able to make sense of this sum using a series of visual arguments that connect three different infinite sums and choose one value to assign to them. Here I try to show visual representations for this argument. While this argument has its inconsistencies, there are more legitimate reasons out there to indicate these values make some sense. In each case, there are valid reasons to assign these values, though the ones here aren't always the best.
This sum has appeared many times on YouTube and has created a lot of controversy and excitement. I am not claiming this to be a set fact; instead, my intent is to show how one standard (though with problems) argument for this claim can be made visual in some sense. If you want to know more about the intricacies involved in this argument, see the videos linked below, especially the ones from Mathologer.
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If you want to find other nice commentaries about this infinite sum, check out the following.
The alternating geometric series argument comes from a proof by The Viewpoints 2000 group from the October 2001 issue of Mathematics Magazine page 320 (jstor.org/stable/2691106 ).
To learn more about animating with manim, check out: https://manim.community
A Visual Attempt at 1 + 2 + 3 + 4 + 5 + ... = -1/12Mathematical Visual Proofs2024-08-04 | I often get requests to give a visual proof of the claim that 1+2+3+4+5+... = -1/12 that is, that the sum of all positive integers is -1/12. One problem with this is that it isn't true using the techniques of real analysis, so visualizing it can be challenging (not to mention that visualizing negative numbers is challenging in and of itself). Another challenge is that people get pretty angry with the various methods used to produce this claim.
However, we are able to make sense of this sum using a series of visual arguments that connect three different infinite sums and choose one value to assign to them. Here I try to show visual representations for this argument. While this argument has its inconsistencies, there are more legitimate reasons out there to indicate these values make some sense. In each case, there are valid reasons to assign these values, though the ones here aren't always the best.
This sum has appeared many times on YouTube and has created a lot of controversy and excitement. I am not claiming this to be a set fact; instead, my intent is to show how one standard (though with problems) argument for this claim can be made visual in some sense. If you want to know more about the intricacies involved in this argument, see the videos linked below, especially the ones from Mathologer.
If you like this video, consider subscribing to the channel or consider buying me a coffee: buymeacoffee.com/visualproofs Thanks!
If you want to find other nice commentaries about this infinite sum, check out the following.
The alternating geometric series argument comes from a proof by The Viewpoints 2000 group from the October 2001 issue of Mathematics Magazine page 320 (jstor.org/stable/2691106 ).
To learn more about animating with manim, check out: https://manim.community
#manim #maths #mathematics #ramanujan #ramanujansummation #infinitesum #sumpositiveintegers #arithmeticmean #series #infiniteseries #divergentseries #divergent #convergent #geometricseries #abelsum #somepiHappy Math Holidays!Mathematical Visual Proofs2024-12-23 | This is a holiday tree built from a cylinder, lines on a cone, and spheres. The tree is topped off with the Koch snowflake. Thank you for your support this year. I hope everyone has a happy holiday season and a wonderful new year. #math #manim #holiday
To learn more about animating with manim, check out: https://manim.communityApproximate Square Roots with Calculus!Mathematical Visual Proofs2024-12-22 | This is a visual technique that uses linear approximation to find the square root of a whole number by finding the equation of the tangent line to points on the square root curve.
To learn more about animating with manim, check out: https://manim.communityApproximate Square Roots Visually!Mathematical Visual Proofs2024-12-20 | This is a visual technique that uses linear approximation to find the square root of a whole number by looking at nested perfect square arrays. Can you prove why this works?
To learn more about animating with manim, check out: https://manim.communityLogarithmic spiral | Spira MirabilisMathematical Visual Proofs2024-12-17 | This is a visualization of a self-similar curve known as a logarithmic spiral or spira mirabilis. To learn more about logarithmic spirals, check out the wikipedia site or mathworld:
To learn more about animating with manim, check out: https://manim.communityNested Powers of 2 Epicycloids (synthwave enumeration)Mathematical Visual Proofs2024-12-11 | This video shows the creation of nested epicycloids with powers of 2 cusps (starting with 2 cusps and ending with 256), generated at rates that are powers of 2. Then the image rotates 3 times before fading out.
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To learn more about epicycloids, check out the wikipedia site:
To learn more about animating with manim, check out: https://manim.communitySeven Proofs Without Words for Summing CubesMathematical Visual Proofs2024-11-27 | This video is a compilation of seven different visual proofs showing the sum formula for the sum of the first n positive cubes that can be found on my channel. This is a new style of video for me inspired by @ThatsAmazing 's trick shots at various levels and @dudeperfect 's soundtracks. I hope you enjoy it. If these visual proofs are too fast to follow completely in this format, the originals are linked below.
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Original sources: Level 1: This animation is based on a visual proofs by Warren Lushbaugh (from an article by Solomon Golomb) in the May 1965 issue of the Mathematical Gazette (doi.org/10.2307/3612319) and, independently, Antonella Cupillari from the October 1989 issue of Mathematics Magazine page 259 (doi.org/10.2307/2689765).
Level 2: This animation is based on a visual proof by Parames Laosinchai from the December 2012 issue of Mathematics Magazine (jstor.org/stable/10.4169/math.mag.85.5.360 page 360).
Level 3: This animation is based on a visual proofs by Warren Lushbaugh (from an article by Solomon Golomb) in the May 1965 issue of the Mathematical Gazette (doi.org/10.2307/3612319).
Level 4: This animation is based on independently discovered, separate visual proofs by J. Barry Love from the March 1977 issue of Mathematics Magazine (jstor.org/stable/2689727), page 74, and Alan L. Fry from the January 1985 issue of Mathematics Magazine (jstor.org/stable/2690228) , page 11.
Level 5: This animation is based on a visual proof by Georg Schrage from the June 1992 issue of Mathematics Magazine (doi.org/10.2307/2691330 - page 185).
Level 6: This animation is based on a visual proof by Tom Edgar from the September 2024 issue of Mathematics Magazine (doi.org/10.1080/0025570X.2024.2379213 page ??).
Level 7: This animation is based on a visual proof by Alfinio Flores from the January 1998 issue of The College Mathematics Journal (jstor.org/stable/2687639 page 61).
To learn more about animating with manim, check out: https://manim.communityNon-differentiabilityMathematical Visual Proofs2024-11-24 | In this short, we show five different graphs of functions with a point where the function is not differentiable.
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To learn more about animating with manim, check out: https://manim.communityCannonball Problem!Mathematical Visual Proofs2024-11-12 | In this short, we show the only nontrivial solution to the cannonball problem, which asks for numbers that are simultaneously square pyramidal and square. The problem gets its name because cannonballs stack nicely in square pyramidal arrays.
Can you prove that 0,1, and 4900 are the only such solutions to the problem?
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To learn more about animating with manim, check out: https://manim.communityVisualizing Derivatives on Multivariable Surface Plots of Average Rates of ChangeMathematical Visual Proofs2024-11-03 | In this video, we investigate the derivative function as the set of discontinuities on the multivariable surface plot of the multivariable function that gives the average rate of change between two points on a single-variable function.
Along the way, we investigate the definition of the derivative of a function at a point and see the key idea behind differential calculus.
This video arose from one of my classes after a conversations with Joe Eichholz - my thanks to Joe for his time.
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To learn more about animating with manim, check out: https://manim.communityContinuous everywhere but differentiable nowhere : Weierstrass Function Visualization!Mathematical Visual Proofs2024-10-18 | This is a visualization of an approximation of the Weierstrass function, which is a function that is continuous everywhere but differentiable nowhere. The curve is defined as an infinite sum and there are several curves like this given different parameters.
To learn more about animating with manim, check out: https://manim.communityMean InequalitiesMathematical Visual Proofs2024-10-10 | This short animated proof demonstrates the two variable mean inequalities for the arithmetic mean, geometric mean, harmonic mean and root mean square (or quadratic mean).
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This animation of the inequalities is based on a visual proof by Roger Nelsen from the June 1987 issue of Mathematics Magazine (jstor.org/stable/2689561) p. 158.
If you like visual proofs of inequalities, see these links:
To learn more about animating with manim, check out: https://manim.communityPythagorean Theorem DissectionMathematical Visual Proofs2024-10-05 | This is a short, animated visual proof of the Pythagorean theorem (the right triangle theorem) where we show how to use Euclid's shear and rotate proof to create a dissection proof.
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The dissection proof was suggested to me by Glen Whitney (studioinfinity.org), and Glen then found a similar dissection in the compendium of Pythagorean theorem proofs from Elisha Loomis (Proof 21 on p. 122 ). (I may receive a small commission at no cost to you for this affiliate link): amzn.to/3RL7rfN
To learn more about animating with manim, check out: https://manim.communityMediant Inequality IMathematical Visual Proofs2024-10-01 | This is a short, animated visual proof demonstrating what one might called the mediant inequality.
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This animation is based on a visual proof by Richard A. Gibbs from the June 1990 issue of Mathematics Magazine (doi.org/10.2307/2691137 - page 172).
To learn more about animating with manim, check out: https://manim.communityPi Times Phi using a Regular Icosagon Area (visual proof)Mathematical Visual Proofs2024-09-28 | In this video, we use a golden triangle to find the area of a regular icosagon sitting inside of the unit circle (the circle with radius 1). From this area formula, we are able to then find an interesting bound on the product of two famous constants: Pi and the golden ratio.
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If you like this video, you might enjoy this compilation of four visual proofs finding the area of a regular dodecagon inscribed in the unit circle: youtu.be/I5IrNug26S8
This animation is based on a visual proof by Roger B. Nelsen from a recent issue of The College Mathematics Journal (doi.org/10.1080/07468342.2024.2347160 ).
To learn more about animating with manim, check out: https://manim.communityCan you explain the pattern?Mathematical Visual Proofs2024-09-27 | This enumeration shows all the tilings of a circular grid divided into n pieces from n = 1 to n = 8 using tiles that cover one or two cells. Can you tell the pattern? Can you prove why or how the Lucas numbers appear? If you are looking for more information about this, I recommend the wonderful textbook Proofs that Really Count: The Art of Combinatorial Proof from Arthur Benjamin and Jennifer Quinn: bookstore.ams.org/dol-27
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If you like this video, check out my others and consider subscribing. Thanks!
#dominotilings #fibonacci #lucas #circulargrid ##countingtiling #count #mathvideo #math #mtbos #manim #animation #iteachmath #mathematics #discretemath #combinatorics #enumeration #synthwave0.bbbb... = 1 (in base b+1) | 9 geometric series dissection proofs without wordsMathematical Visual Proofs2024-09-22 | This video is a compilation of nine shorter videos I have created showing dissection proofs for infinite geometric series with ratio of the form 1/n and first term 1/n. One interpretation of these series is that 0.bbbb... = 1 in base b+1 .
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For another compilation of geometric series dissections (with minimal overlaps), check out this video: youtu.be/JteQEN1XPyc
This is a compilation of nine shorts (most with words). If you want to see those, the links are below (along with attribution to the original ``proof without words" author).
00:06 Infinite sum of powers of 1/2 (0.111... = 1 in base 2): youtube.com/shorts/iVLE8gEJfPA This animation is based on a visual proof by Warren Page from the September 1981 issue of Mathematics Magazine, (page 201 - jstor.org/stable/2689632 ).
00:38 Infinite sum of powers of 1/3 (0.222... = 1 in base 3): youtube.com/shorts/GwIVlNRV-M0 This animation is based on a proof by Elizabeth M. Markham from the October 1993 issue of Mathematics Magazine page 242 (doi.org/10.2307/2690738).
01:20 Infinite sum of powers of 1/4 (0.333... = 1 in base 4): youtube.com/shorts/qk1IPvvWfr0 This animation is based on a proof by Sunday A. Ajose from the June 1994 issue of Mathematics Magazine (jstor.org/stable/2690616 page 230).
01:55 Infinite sum of powers of 1/5 (0.444... = 1 in base 5): youtube.com/shorts/ltKZJ8wumUI This animation is based on a proof by Elizabeth M. Markham from the October 1993 issue of Mathematics Magazine page 242 (doi.org/10.2307/2690738).
02:40 Infinite sum of powers of 1/6 (0.555... = 1 in base 6): youtube.com/shorts/T2Mi0AUIKJY This animation is based on a proof by James Tanton from the March 2008 issue of The College Mathematics Journal page 106. (jstor.org/stable/27646594).
05:00 Infinite sum of powers of 1/9 (0.888... = 1 in base 9): youtube.com/shorts/a8YMq_q4HRs This animation is inspired by the a proof by Elizabeth M. Markham from the October 1993 issue of Mathematics Magazine page 242 (doi.org/10.2307/2690738).
05:50 Infinite sum of powers of 1/10 (0.999... = 1 in base 10): youtube.com/shorts/XJtjU_Ipjno This animation is based on a proof by James Tanton from the March 2008 issue of The College Mathematics Journal page 106. (jstor.org/stable/27646594).
To learn more about animating with manim, check out: https://manim.community ___________________________________ Music: Wanderer by Alexander Nakarada (CreatorChords) | creatorchords.com Music promoted by free-stock-music.com Creative Commons / Attribution 4.0 International (CC BY 4.0) creativecommons.org/licenses/by/4.0Dancing tilings - why this pattern?Mathematical Visual Proofs2024-09-17 | This short shows the enumeration of all the domino tilings of the (2 x n)-grid for n=1 to n=8. Can you tell the pattern? Can you prove why or how the Fibonacci numbers (perhaps more aptly called the Virahanka numbers) appear?
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If you are looking for more information about this, I recommend this fantastic video by : youtu.be/Ct7oltmdJrM or the wonderful textbook Proofs that Really Count: The Art of Combinatorial Proof from Arthur Benjamin and Jennifer Quinn: bookstore.ams.org/dol-27
To learn more about animating with manim, check out: https://manim.communitySums of Sums of Squares (visual proof)Mathematical Visual Proofs2024-09-15 | This is a short, animated visual proof for the sum of the sum of squares formula using a wonderful visual proof computing the sum of squares formula.
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This animation is based on a visual proof by C.G. Wastun according to Roger Nelsen in his second Proof without Words compendium (page 91) : bookstore.ams.org/view?ProductCode=CLRM/14
This first visual proof animation is based on (independently discovered) visual proofs by Dan Kalman from the March 1991 issue of The College Mathematics Journal (jstor.org/stable/2686447) and Martin Gardner from the October 1973 Scientific American (jstor.org/stable/24923225).
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#math #manim #mathvideo #sumofsquares #mtbos #manim #animation #theorem #pww #proofwithoutwords #visualproof #proof #iteachmath #finitesums #discretemath #induction #sumsumsquares #partialsumsPythagorean Theorem - Behold!Mathematical Visual Proofs2024-09-08 | This is a short, animated visual proof of the Pythagorean theorem (the right triangle theorem) following essentially Bhāskara's proof (Behold!). This theorem states the square of the hypotenuse of a right triangle is equal to the sum of squares of the two other side lengths.
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This animation is based on a proof due to Bhāskara. For a static version of this proof, see Roger Nelsen's first "Proof Without Words: Exercises in Visual Thinking" compendium (page 4). You can also check out Howard Eves' "Great Moments in Mathematics (Before 1650)" page 29-32.
Check out Roger's book on Amazon (affiliate link to follow; I may receive a small commission): amzn.to/3SjsqEh
To learn more about animating with manim, check out: https://manim.communityChaos Game finds the Mandelbrot QuintetMathematical Visual Proofs2024-09-03 | In this video, we show how to use a random process of iteratively applying five affine transformations in the real plane to generate a 5-rep-tile known as the Mandelbrot Quintet. What happens if you do something similar with different affine transformations?
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This animation was inspired by an article written by Lorelei Koss that appeared in the Proceedings of Bridges 2015: archive.bridgesmathart.org/2015/bridges2015-423.pdf . For more information, you should also check out the related article "Fractal Tilings in the Plane" by Richard Darst, Judith Palagallo and Thomas Price from the February 1998 Mathematics Magazine: jstor.org/stable/2691339
To learn more about animating with manim, check out: https://manim.community0.5555… = 1 (in base 6)Mathematical Visual Proofs2024-08-30 | This is a short, animated visual proof showing the sum of the infinite geometric series with first term 5/6 and ratio 1/6, which in turn allows us to compute the sum of the series of powers of 1/6 and determine an interesting base 6 representation of 1.
If you like this video, consider subscribing to the channel or consider buying me a coffee: buymeacoffee.com/VisualProofs. Thanks!
To learn more about animating with manim, check out: https://manim.communityTwo Geometric Series in an Isosceles Trapezoid (visual proof without words)Mathematical Visual Proofs2024-08-24 | This is a short, animated visual proof demonstrating the sum of two infinite geometric series using dissection proofs in an isosceles trapezoid. In particular, we show how to find the sum of powers of 1/4 and the alternating sum of powers of 1/2 using the isosceles trapezoid. Geometric series are important for many results in calculus, discrete mathematics, and combinatorics.
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______________________________ Music in this video: Traveling Around The World by Alex-Productions | https://onsound.eu/ Music promoted by free-stock-music.com Creative Commons / Attribution 3.0 Unported License (CC BY 3.0) creativecommons.org/licenses/by/3.0/deed.en_USParallelogram Area from Side Angle SideMathematical Visual Proofs2024-08-21 | This is a short animation showing a standard fact about how to find the area of a parallelogram using the lengths of the two sides and the angle between them. This fact will be used in future videos showing the AM-GM inequality and the Cauchy Schwarz inequality (and possibly others).
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To learn more about animating with manim, check out: https://manim.communityTop 10 Math ConstantsMathematical Visual Proofs2024-08-17 | In this video, we show visualizations of ten classic mathematical constants:
1) The square root of 2 as the length of the diagonal of a 1 by 1 square. 2) Pi as the area of the circle with radius 1. 3) Tau as the circumference of the circle with radius 1. 4) The golden ratio as the number satisfying (x+1)/x=x/1. 5) The square root of 3 as the altitude or area of an equilateral triangle with side length 2. 6) Euler's number e as the ending x-coordinate yielding the area under the curve of 1/x starting at x=1. 7) The silver ratio as the horizontal length across the regular octagon with side length 1 or the area of the largest rectangle inside the same regular octagon. 8) The natural logarithm of 2, ln(2), as the sum of the convergent alternating harmonic series. 9) The plastic ratio as the limit of the ratio of side lengths in a spiral of equilateral triangles with side lengths dictated by the Padovan sequence. 10) The Euler-Mascheroni constant as the difference between the harmonic series and the area under the curve y=1/x from 1 to infinity.
If you like this video, consider subscribing to the channel or consider buying me a coffee: buymeacoffee.com/VisualProofs. Thanks!
To learn more about animating with manim, check out: https://manim.communityAM-GM Inequality via negative spaceMathematical Visual Proofs2024-08-14 | This is a short, animated visual proof demonstrating the arithmetic mean geometric mean inequality using algebraic areas and the Side-Angle-Side formula for a parallelogram.
If you like this video, consider subscribing to the channel or consider buying me a coffee: buymeacoffee.com/VisualProofs. Thanks!
To learn more about animating with manim, check out: https://manim.communitySum of Cubes VII (visual proof without words)Mathematical Visual Proofs2024-08-11 | This is a short, animated (wordless) visual proof demonstrating the sum of the first n positive cubes by rearranging two stacks of cubic arrays.
If you like this video, consider subscribing to the channel or consider buying me a coffee: buymeacoffee.com/VisualProofs. Thanks!
Here are six other visual proofs of sum of cubes formulas:
This animation is based on a visual proof by Tom Edgar from the September 2024 issue of Mathematics Magazine (doi.org/10.1080/0025570X.2024.2379213 page ??).
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#mathshorts #mathvideo #math #calculus #mtbos #manim #animation #theorem #pww #proofwithoutwords #visualproof #proof #iteachmath #finitesums #discretemath #calculus #sum #induction #faulhaber #sumofcubes #cubes ___________________________________________ Music in this video: Epic Cyberpunk | GLORY by Alex-Productions | https://onsound.eu/ Music promoted by free-stock-music.com Creative Commons / Attribution 3.0 Unported License (CC BY 3.0) creativecommons.org/licenses/by/3.0/deed.en_US0.8888… = 1 (in base 9)Mathematical Visual Proofs2024-08-08 | This is a short, animated visual proof showing the sum of the infinite geometric series with first term 8/9 and ratio 1/9, which in turn allows us to compute the sum of the series of powers of 1/9 and determine an interesting base 9 representation of 1.
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For a longer, wordless version (more dramatic) of this animation see youtu.be/C4t_ps3VKvI
This animation is inspired by the a proof by Elizabeth M. Markham from the October 1993 issue of Mathematics Magazine page 242 (doi.org/10.2307/2690738).
To learn more about animating with manim, check out: https://manim.communityTrapezoid Area Visual ProofMathematical Visual Proofs2024-08-06 | This is a short animation showing a standard fact about how to find the area of a trapezoid by finding a triangle with the same area.
If you like this video, consider subscribing to the channel or consider buying me a coffee: buymeacoffee.com/VisualProofs. Thanks!
Here is the original video in wide-format, wordless, with dramatic music: youtu.be/4ZypJJmd5ZY
Here is a related visual proof for the area of a parallelogram: youtu.be/QjWbBexfJvw
To learn more about animating with manim, check out: https://manim.communityTrig Double Angle Formulas from Semicircle (visual proof)Mathematical Visual Proofs2024-07-27 | This is a short, animated visual proof of the Double angle identities for sine and cosine. To get the formulas we use a semicircle diagram and rely on similarity of two right triangles formed inside.
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For another visual proof of this fact using the laws of sines and cosines, check out this animation: youtu.be/0ggGQ96eaiE
This animation is based on a visual proof by Roger B. Nelsen from the January 1989 issue of The College Mathematics Journal (jstor.org/stable/2686819 - page 51).
To learn more about animating with manim, check out: https://manim.communityTen Mortal Math ConstantsMathematical Visual Proofs2024-07-22 | In this video, we show visualizations of ten classic mathematical constants:
1) The square root of 2 as the length of the diagonal of a 1 by 1 square. 2) Pi as the area of the circle with radius 1. 3) Tau as the circumference of the circle with radius 1. 4) The golden ratio as the number satisfying (x+1)/x=x/1. 5) The square root of 3 as the altitude or area of an equilateral triangle with side length 2. 6) Euler's number e as the ending x-coordinate yielding the area under the curve of 1/x starting at x=1. 7) The silver ratio as the horizontal length across the regular octagon with side length 1 or the area of the largest rectangle inside the same regular octagon. 8) The natural logarithm of 2, ln(2), as the sum of the convergent alternating harmonic series. 9) The plastic ratio as the limit of the ratio of side lengths in a spiral of equilateral triangles with side lengths dictated by the Padovan sequence. 10) The Euler-Mascheroni constant as the difference between the harmonic series and the area under the curve y=1/x from 1 to infinity.
If you like this video, consider subscribing to the channel or consider buying me a coffee: buymeacoffee.com/VisualProofs. Thanks!
To learn more about animating with manim, check out: https://manim.communityInductive factorial sum visual proofMathematical Visual Proofs2024-07-15 | This is a short, animated visual proof demonstrating a finite sum involving products of factorials. The proof exploits the classic inductive proof of the formula in question.
If you like this video, consider subscribing to the channel or consider buying me a coffee: buymeacoffee.com/VisualProofs. Thanks!
This animation is based on a proofs by Tom Edgar from the December 2016 issue of Mathematics Magazine page 338 (doi.org/10.4169/math.mag.89.5.338).
If you want to see a longer version, with an accompanying explanation, check out youtu.be/FE0Vl4zm20I
To learn more about animating with manim, check out: https://manim.communityTop four visual proofs?Mathematical Visual Proofs2024-07-10 | In this short, we show animations of four of the most famous proofs without words: the formula for the sum of the first n integers; the pythagorean theorem using negative space/sliding rectangles/Chou pei suan ching; the formula for the sum of the first n odd integers; and the infinite geometric series of positive powers of 1/2 (using a rectangle/square dissection of a unit area square). We include brief justifications for these visual proofs.
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The first proof was known to the ancient greeks (cited by Martin Gardner), the second proof is adapted from the Chou pei suan ching (around 200 BCE according to Roger Nelsen), the third is attributed to Nicomachus of Gerasa by Roger Nelsen, and the final one is attributed to Warren Page (from the September 1981 issue of Mathematics Magazine, page 201 - jstor.org/stable/2689632 ). The first three can all be found in Roger Nelsen's first compendium, "Proofs Without Words: Exercises in Visual Thinking: bookstore.ams.org/view?ProductCode=CLRM/1 .
To learn more about animating with manim, check out: https://manim.communityTwo Infinite Series Sums from Regular Polygons (visual proof)Mathematical Visual Proofs2024-07-07 | This is a short, animated visual proof computing the sums of two series - one of reciprocals of triangular numbers (i.e., certain binomial coefficients) and the other a classic series that is used to demonstrate telescoping series.
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This animation is based on a visual proof by Paul Stephenson from the December 2022 issue of Mathematics Magazine (doi.org/10.1080/0025570X.2022.2126173 page 572 ).
To learn more about animating with manim, check out: https://manim.communityProduct of chords?Mathematical Visual Proofs2024-07-01 | This short animation shows chords connecting n equally space points to one of those points on a unit circle and computes the product of the chord lengths. Do you have a conjecture based on this? Can you prove it?
This animation is based on a famous problem that has been discussed in numerous places. In particular, a great reference for this problem and related ones (with a fantastic bibliography) is the source Chords of an Ellipse, Lucas Polynomials, and Cubic Equations in Issue 8 of the 2020 American Mathematical Monthly (doi.org/10.1080/00029890.2020.1785253) by Ben Blum-Smith and Japheth Wood. You can also find the source here: arxiv.org/abs/1810.00492.
For more about using manim, see https://www.manim.community/.Arithmetic Mean-Geometric Mean Visual Proof CompilationMathematical Visual Proofs2024-06-30 | This video is a compilation of seven shorter videos that I have created showing various visual proofs without words of the famous AM-GM inequality, which states that the arithmetic mean of two numbers (a+b)/2 is greater than or equal to the geometric mean of the two numbers square root of a times b.
To see the original videos (in shorter form and sometimes with words/explanations), check the links below. Of course there are many other visual proofs of this amazing fact, but these are my favorite seven.
Let me know your favorite in the comments!
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Here are the original series videos (along with attribution; for more detailed attribution, see the original videos):
To learn more about animating with manim, check out: https://manim.communityHappy Tau Day!Mathematical Visual Proofs2024-06-27 | In this short video, we show one way to visualize the constant tau, which is twice pi, as the area between the curves 1/(1+x^2) and its negation over the entire real line.
To learn more about animating with manim, check out: https://manim.communityPythagorean theorem from a (semi) circle!Mathematical Visual Proofs2024-06-24 | This is a short, animated visual proof of the Pythagorean theorem (the right triangle theorem) using the semicircle and Thales triangle theorem. This theorem states the square of the hypotenuse of a right triangle is equal to the sum of squares of the two other side lengths.
This animation is based on a proof due to Michael Hardy from the November, 1986 issue of The College Math Journal (doi.org/10.2307/2686255).
To learn more about animating with manim, check out: https://manim.communitySum Geometric Series with Ratio 1/2 in Rectangles (visual proofs)Mathematical Visual Proofs2024-06-22 | In this video, we show an animated version of a recent proof without words that finds the sum of the geometric series with first term 1/root(2)+1/2 and ratio 1/2 using the unit square. Then we show how to find other geometric series sums with ratio 1/2 using different sizes of rectangles. Careful, the final bonus question might require a different technique than rotating :)
If you like this video, consider subscribing to the channel or consider buying me a coffee: buymeacoffee.com/VisualProofs. Thanks!
To learn more about animating with manim, check out: https://manim.community0.66666… = 1 (in base 7)Mathematical Visual Proofs2024-06-17 | This is a short, animated visual proof showing the sum of the infinite geometric series with first term 6/7 and ratio 1/7, which in turn allows us to compute the sum of the series of powers of 1/7 and determine an interesting base 7 representation of 1.
If you like this video, consider subscribing to the channel or consider buying me a coffee: buymeacoffee.com/VisualProofs. Thanks!
This animation is based on a proof by Stephan Berendonk (2020) from the November 2020 issue of The College Mathematics Journal, (doi.org/10.1080/07468342.2020.1830649 p. 385)
To learn more about animating with manim, check out: https://manim.communityA Factorial Sum Produces the Factorial Number System (visual proof)Mathematical Visual Proofs2024-06-15 | This is a short, animated visual proof demonstrating a finite sum involving products of factorials. The proof exploits the classic inductive proof of the formula in question. As a bonus, we discuss the factorial number system and show how the formula can be used to count up in this system.
If you like this video, consider subscribing to the channel or consider buying me a coffee: buymeacoffee.com/VisualProofs. Thanks!
This animation is based on a proofs by Tom Edgar from the December 2016 issue of Mathematics Magazine page 338 (doi.org/10.4169/math.mag.89.5.338).
To learn more about animating with manim, check out: https://manim.communityAlternating Geometric Series SumMathematical Visual Proofs2024-06-13 | This is a short, animated visual proof demonstrating the infinite alternating geometric series formula for any positive ratio r with r less than 1 and with positive first term a. This series is important for many results in calculus, discrete mathematics, and combinatorics. To buy me a coffee, head over to buymeacoffee.com/VisualProofs Thanks!
For a slower, wide format version of this video (without words), see youtu.be/Qa0bOHYjnW0
This animation is based on a proof by The Viewpoints 2000 group from the October 2001 issue of Mathematics Magazine page 320 (jstor.org/stable/2691106 ).
To learn more about animating with manim, check out: https://manim.communitySpiral of TheodorusMathematical Visual Proofs2024-06-10 | This is a short, animated visual proof demonstrating how to construct square roots of any positive integer using the Spiral of Theodorus
To learn more about animating with manim, check out: https://manim.communityTerdragon from the Chaos Game (visual fractal construction from iterated function system)Mathematical Visual Proofs2024-06-08 | In this video, we show how to use a random process of iteratively applying three affine transformations in the real plane to generate a 3-rep-tile known as the Terragon. What happens if you do something similar with different affine linear transformations?
For more information, you should also check out the related article "Fractal Tilings in the Plane" by Richard Darst, Judith Palagallo and Thomas Price from the February 1998 Mathematics Magazine: jstor.org/stable/2691339
To learn more about animating with manim, check out: https://manim.community
_________________________________________ Music in this video: The Sun Will Rise by Vlad Gluschenko | soundcloud.com/vgl9 Music promoted by free-stock-music.com Creative Commons / Attribution 3.0 Unported License (CC BY 3.0) creativecommons.org/licenses/by/3.0/deed.en_USSum of a Positive Number and its Reciprocal from CalculusMathematical Visual Proofs2024-06-06 | This is a short, animated visual proof demonstrating that sum of a positive real number and its reciprocal is always greater than or equal to 2.
It turns out that this theorem is equivalent to the Arithmetic Mean-Geometric Mean inequality. The equivalence is implied by the following two proofs: youtu.be/62G9fak1vyk youtu.be/IghOHBl0Do8
To learn more about animating with manim, check out: https://manim.communityGarfield’s Pythagorean ProofMathematical Visual Proofs2024-06-03 | This is a short, animated visual proof of the Pythagorean theorem (the right triangle theorem) using the trapezoid that is now attributed to President James Garfield. This theorem states the square of the hypotenuse of a right triangle is equal to the sum of squares of the two other side lengths.
This animation is based on a proof due to James A. Garfield. For a static version of this proof, see Roger Nelsen's first "Proof Without Words: Exercises in Visual Thinking" compendium (page 7) : bookstore.ams.org/clrm-1. You can also check out Howard Eves' "Great Moments in Mathematics (Before 1650)" page 34-36.
To learn more about animating with manim, check out: https://manim.communityRoot 2 is Irrational from Isosceles Triangle (visual proof)Mathematical Visual Proofs2024-06-01 | In this short, we use a famous argument by Tom Apostol to prove that the square root of two is irrational by infinite descent using a right isosceles triangle. We also go a bit further and show how this proof hints at the number theoretic construction of the convergents of the square root of two, which are the best rational approximations of root 2.
If you like this video, consider subscribing to the channel or consider buying me a coffee: buymeacoffee.com/VisualProofs. Thanks!
For an alternate visual proof of this fact, see this video: youtu.be/-dbzvN4jnfY
This animation is based on an argument due to Tom Apostol from issue 9 of the 2000 American Mathematical Monthly: doi.org/10.1080/00029890.2000.12005280
To learn more about the convergents argument and the relationship between this proof and convergents, see this wonderful article by Doron Zeilberger: https://sites.math.rutgers.edu/~zeilberg/mamarim/mamarimPDF/sqrt2.pdf and here you can learn more about convergents: en.wikipedia.org/wiki/Continued_fraction#Convergents
To learn more about animating with manim, check out: https://manim.communitySums of Fibonacci SquaresMathematical Visual Proofs2024-05-30 | This is a short, animated visual proof demonstrating the sum of the squares of the first n consecutive Fibonacci numbers.
This animation is based on a proof by Alfred Brouusseau from "A Primer for the Fibonacci Numbers by M. Bicknell and V.E. Hoggatt Jr (eds.). You can also find this proof in Roger Nelsen's first Proof Without Words compendium (page 83).
Get Nelsen's Amazing Book (Affiliate link so I may receive a commission): amzn.to/3QF6Zvz