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Category Archives: Fun Stuff
What’s an eigenface?
With the recent korean wave, we get to see lots of Korean pop, tv, movie stars in the media. But I found that I can never tell them apart. Especially, the ladies, tall, thin, beautiful but too homogenous. (Of course, … Continue reading
Posted in Applications, Fun Stuff, Linear Algebra
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Whither the golden ratio
According to this report from the Guardian, someone claims that the golden ratio pleases the eye because of scanning ratios, i.e. how fast the eye scans things horizontally versus vertically. The actual paper is supposed to be free access (with … Continue reading
Posted in Fun Stuff
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Collective Nouns for Mathematicians
A creative colleague got me started and I just can’t stop. Of course the most apt term would be “a set of mathematicians”. But how about others, according to their fields? Ignoring the obvious alliterative ones like “a set of … Continue reading
Posted in Fun Stuff
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4 clicks to Mathematics
I learn this game from watching Tim Chartier’s video. (The original game was 5 clicks to Jesus but in this age of religious sensitivity … ) So this is the game, go to Wikipedia and click random article on the … Continue reading
Posted in Fun Stuff, Technology, Web
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The Feynman Problem Solving Algorithm
according to here is this 1) Write down the problem 2) Think very hard 3) Write down the answer
Posted in Fun Stuff, Problems, Quotes/People
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Math and Movies
A huge collection of video clips of movies and tv programmes that feature some mathematics. Some of which are a hoot. I especially love the one from Wizard of OZ where Scarecrow proclaims “the sum of the square root of … Continue reading
Posted in Fun Stuff
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Dodecagon
Funny cartoon from savage chickens.link
Posted in Fun Stuff, Geometry/Topology
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Calligraphy
The Chinese character that appears on the left of the logo is a stylized version of 数 which means “to count” (as a verb) or a “number/value/sum” (as a noun). The Chinese word for mathematics is 数学, the art or … Continue reading
Posted in Fun Stuff
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Turing Doodle
I was supposed to wake up early before my two year old boy so that I could get some work done, but alas, I got distracted by the neat little Turing machine puzzle put up by the guys at google. … Continue reading
Posted in Fun Stuff, Number Theory, Quotes/People, Technology
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Coincidences
I’ll be visiting China tomorrow and my mum kindly handed me a stack of RMB (China’s currency) that was left-over previously. I took a quick count and it totals exactly 1729 Yuan. What are the odds?
Posted in Fun Stuff
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It’s Pi Day today
A little creative tinkering yielded this mnemonic for [tex]\pi[/tex] Pi (apologies, latex died) to 15 places. “How I need a drink, alcoholic of course, after the heavy lectures involving Euclid’s algorithm” I’ve substituted “quantum mechanics” with “Euclid’s algorithm”, not exactly … Continue reading
Posted in Fun Stuff, Number Theory, Teaching
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Homework
We have seen textbooks that only gives solutions to odd-numbered exercises. But have you seen a number theory text with the following exercises? 1) Prove that [tex]x^3 + y^3 = z^3[/tex] has no non-trivial solutions in integers. 2) Prove that … Continue reading
Posted in Books, Fun Stuff, Quotes/People
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Mnemonic Trig (or Trick)
[tex]\cos (3x) = 4\cos^3(x) -3 \cos(x)[/tex] The way to remember it in Hokkien (a local dialect commonly spoken in Singapore, Taiwan and southern parts of China): Cor Sah ($1.30) = Si Cor Sah ($4.30) – Sah Cor ($3). You can … Continue reading
Posted in Calculus/Analysis, Fun Stuff, Trigonometry
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autologlyphs
morphing maths with art by Henry Segerman. Cool stuff. I especially liked the mirror symmetry one. As usual, found via J. Cook.
Posted in Fun Stuff, General
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Bell Numbers
defined as [tex] \displaystyle B(n) = \sum_{k=0}^n \left\{ {n \atop k}\right\}[/tex] counts the total number of ways to partition n distinct objects into disjoint subsets (or blocks) where [tex] \displaystyle \left\{ {n \atop k}\right\} [/tex] is the well known Stirling … Continue reading
Posted in Combinatorics, Fun Stuff
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pendulum waves
Great video illustrating waves with 15 pendulums. Watch to the end to see the pendulums make one complete cycle. First saw this via john d cook.
Posted in Fun Stuff, Physics, Teaching
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Soap bubbles and current research
That’s the title of Frank Morgan’s talk today. The main takeaway is how, (motivated?) students can be exposed to interesting problems and work on current research. For example, it has been known for almost 2000 years that the circle in … Continue reading
Posted in Fun Stuff, Geometry/Topology, Teaching
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A $23 million dollar book
A very interesting post. http://www.michaeleisen.org/blog/?p=358 It is not merely the astronomical price tag but the clever detective work that figured out what lead to the crazy price and is a good example of how algorithms can go wrong. Finally it … Continue reading
Posted in Books, Fun Stuff, General, Linear Algebra
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Math in movies
Here’s a collection of snippets of movies where maths appears in one way or another. A few notable ones are missing perhaps due to the unavailability of clips. A few off the top of my head are Good Will Hunting, … Continue reading
Posted in Fun Stuff, General
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12 Days of Christmas
Nice problem and solution at squarecirclez about counting the total number of presents. Triangular numbers appears! It seems that this year’s Simpsons Christmas special was a live action parody/tribute to Sesame Street and the Muppets. It had them singing the … Continue reading
Posted in Calculus/Analysis, Fun Stuff, Number Theory, Problems, Teaching, Technology
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