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# Posts

### April 23, 2014

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Only image ever taken of a transit of a space shuttle (Atlantis) and the Hubble Space Telescope (HST) in front of the Sun.

### April 22, 2014

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(Un poco antes de tiempo, pero con la aquiescencia del anfitrión y por una buena causa). Iniciativas de divulgación científica, por suerte, hay muchas y muy buenas. Lo que distingue a este concurso es que (1) Quienes divulgan son estudiantes, (2) Éstos lo hacen voluntariamente y (3) Expertos comunicadores les dan consejos. ¿Quieres saber cómo se utilizan matemáticas para ...corregir la cámara de un móvil el movimiento de tu mano? […]

### April 20, 2014

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I did the case $p=1$ here. The generalization to higher $p$ may involve higher-order derivatives as follows: \begin{align}K_p &= \int_0^{\pi/2} dx \frac{x^{2 p}}{1+\cos^2{x}} = \frac1{2^{4 p-1}} \int_{-\pi}^{\pi} dy \frac{y^{2 p}}{3+\cos{y}} \end{align} So define, as before, $$J(a) = \int_{-\pi}^{\pi} dy \frac{e^{i a y}}{3+\cos{y}}$$ Then $$K_p = \frac{(-1)^p}{2^{4 p-1}} \left [\frac{d^{2 p}}{da^{2 p}} J(a) \right ]_{a=0}$$ […]

### April 17, 2014

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Ha! I can’t believe I’m writing about this, but I think it’s important for those who are beginning a new chapter in their professional journey: a first tenure-track job, a new post-doc, a first/second year grad student. Learning to say “No” … Continue reading →

### April 14, 2014

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This example aims to demonstrate our inability to fully grasp exponential functions. Our action hero stands on a platform inside an empty 4000 litre water tank. At the very bottom of the tank lies a magic drop of water. Invisible to the eye now, it doubles in size every 10 seconds. Although the growth rate is constant, for a long time we see no change. But there's a well known limit, the capacity of the tank. Once he realises that water is rising exponentially, poor pixellated Chris has no […]
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The folks at Pixar are widely known as some of the world's best storytellers and animators. They are perhaps less recognized as some of the most innovative math whizzes around. Pixar Research Lead Tony DeRose delves into the math behind the animations, explaining how arithmetic, trigonometry and geometry help bring Woody and the rest of your favorite characters to life.
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One deck. Fifty-two cards. How many arrangements? Let's put it this way: Any time you pick up a well shuffled deck, you are almost certainly holding an arrangement of cards that has never before existed and might not exist again. Yannay Khaikin explains how factorials allow us to pinpoint the exact (very large) number of permutations in a standard deck of cards.

### April 11, 2014

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Linked to australian curriculum standards. Students need to convert units, multiply and use decimals and percentages. Problem solving which has a number of levels to extend students.

### April 07, 2014

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A long time ago … I was an enthusiastic graduate student in mathematics. I had finally figured out that mathematics was what I would be doing with myself. I would continue to learn more mathematics and I would finally be … Continue reading →

### April 06, 2014

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Named after the Greek Mathematician. This classic method of finding prime numbers is also great for teaching about factors and multiples. The visnos sieve allows for multi colored squares this allows identification of any numbers prime factors.
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See equivalent fractions and where they fit on the number line.
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This activity can be used to explore equivalence between fractions, decimals and percentages. Fractions are represented by layers of bricks which can be turned on or off. It easy to show why for example that one half is equal to two-quarters or four-eighths.

### April 05, 2014

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Made for the Distracted Driving campaign in the US, this video offers a graphic depiction of the result of distracted driving.
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Official US Government Website for Distracted Driving. Includes statistics.

### April 04, 2014

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Fox News continues to be a great source of misleading graphs. This time a column graph with no scale, a displaced y-axis.
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A chart from Fox News (US) where the data points have not been plotted correctly.
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I wanted to write directly to those students who are about to start graduate school in the fall and to those who are in their first year of graduate work. The transition to graduate school involves so many changes at … Continue reading →
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#NCTMNOLA is almost on us and it remains to be seen how much recapping will happen. I’ve posted an excerpt of my own schedule on my personal blog and I intend to recap a lot of it. I have conflicts with great sessions in every slot, though, so it’d be great to get some of […]
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Smart and witty, jam-packed with augmented-reality graphics and fascinating history, this film, presented by Professor David Spiegelhalter, tries to pin down what chance is and how it works in the real world.
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Documentary which takes viewers on a rollercoaster ride through the wonderful world of statistics to explore the remarkable power they have to change our understanding of the world, presented by superstar boffin Professor Hans Rosling, whose eye-opening, mind-expanding and funny online lectures have made him an international internet legend.
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Use and make accurate scale drawings of rooms or places. A video and activities about scale drawings.

### April 03, 2014

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Five short typical test questions involving permutations.

### March 31, 2014

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Ya teneis disponible un resumen con las entradas del Carnaval de este mes. Adelante con las votaciones http://matesdedavid.blogspot.com.es/2014/03/resumen-edicion-52-emmy-noether.html

### March 30, 2014

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Participación de PIkasle en la Edición 5.2 del Carnaval de Matemáticascuyo anfitrión es Matesdedavid. Léelo en: http://pikasle.com/es/2014/03/topologia-bilbaina/
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La última vez que se mantuvieron unidos los números con las estrellas del firmamento fue debido a las cadenas de Dedekind. Con su maravilloso libro “¿Qué son y para qué sirven los números?”, se embarcó en el empeño de construir una teoría de los números en base a transformaciones casi mágicas. Seguir leyendo
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La estructura de Kelvin, constituida por octaedros truncados, esconde figuras geometrícas que podría ser interesante descubrir, ¿te animas?
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Segunda entrada de "Guirnalda matemática" para el Carnaval, una propiedad de las cuerdas focales de las cónicas: Media armónica focal
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¿Cuántas calorías espero que me suponga el capricho? La respuesta en la entrada "¿Cuántos huevos Kinder tendré que comer?" del nuestro blog Blioquinfo, con la que participamos en el Carnaval v5.2.

### March 29, 2014

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En el presente texto se exponen las consecuencias lógicas de las mediciones que implican, en el ámbito de la Física, la validación (aunque no verificación) de una serie de interpretaciones determinísticas. Sobre las mediciones y sus consecuencias deterministas.