# Posts

### August 21, 2014

+

11:50 AM | Track your sleep with Sense

Entering the market of self-surveillance for sleep, via Kickstarter, Sense promises to be a smarter tracker that you don't have …Tags: Kickstarter, sleep

+

11:26 AM | And a Few More Puzzles

If the prior puzzle was a bit too much for you, a few below that are more manageable...Been reading "Mathematical Curiosities," new from Alfred Posamentier and Ingmar Lehmann. It is, as the subtitle suggests, "a treasure trove of unexpected entertainments" -- especially entertaining if you have a geometry bias.In the middle of it come 90 "curious problems with curious solutions." Several of these are classics with which you'll be familiar, and others are a little fresher, all interesting. […]

+

11:07 AM | August 21, 2014

Solution at the bottom of this page.Like this problem? Try our Contest Problem Book series!Exercise your mind daily with a problem from the AMC-8, AMC-10, or AMC-12, provided by Mathematical Association of America's American Mathematics Competitions.

+

10:47 AM | How Much Weight Does Wet Hair Add?

Is it true that you weigh more soaking wet? And if so, how MUCH more? Find out and do it in your classroom too!

+

The art of writing a scientific biography is a very difficult one and has been mastered by very few writers so far. The task becomes all the more difficult if the subject is somewhat controversial and non-conventional. However, all these factors didn't deter Rbecca Skloot in her fabulous attempt at telling the story of an Read more

+

8:41 AM | Speed Maths Challenge Cape Town 2014

After months of preparation and anticipation, our big day had arrived – the first Speed Maths Challenge hosted by Vedic Maths Forum South Africa - the venue, Turfhall Primary School in Penlyn Estate, Cape Town – date, 2nd August 2014.There was much excitement, some nerves and loads of enthusiasm on the part of learners, parents, teachers and even us, the organisers. Some learners were waiting at the hall a whole hour before the event! All 5 schools - Turfhall Primary, Rylands Primary,
[…]

+

8:23 AM | God and Unemployment

‘When I began my research interviewing unemployed and underemployed Southern Californians in 2011, I did not expect that their religious views would turn out to be so important. Previous studies of unemployed Americans have scarcely commented on their spirituality. But over and over I heard my interviewees say, as an unemployed IT worker put it, […]

+

7:22 AM | Feltron Annual Report 2013

In his ninth edition of the personal report, Nicholas Felton looks at communication through his phone, email, Facebook, and physical …Tags: Nicholas Felton, report

+

7:00 AM | 7808

7808 = 2 x 2 x 2 x 2 x 2 x 2 x 2 x 61.7808 is the number of 4 x 4 sliding-block puzzle positions that require exactly 12 moves to solve starting with the hole in a corner (A089484).7808 is 101201012 in base 3 (A043589). Reversing the base-3 representation of 7808 produces twice the original number (A173951).7808 is the sum of two positive fifth powers (A003347). It is the sum of the fifth powers of the digits of 26 (A055014).7808 has a representation as a sum of two squares: 7808 = 82 +
[…]

+

Five circles in a square – GeoGebra Animation The green square has area of 4. The center blue circle is tangent to each of the other blue circles, which are tangent to the green square. Let the radius of the center circle be R, and the radius of the other circles be r. Write [...]

+

5:29 AM | 2014 PUP Mathmax

Share it!(Polytechnic University of the Philippines) PUP Mathmax is an annual Mathematics contest organized by Polytechnic University of the Philippines. This year the schedule of the event will be on September 27, 2014 at PUP...
The post 2014 PUP Mathmax appeared first on Techie Math Teacher.

+

Le sue lezioni erano molto confuse, saltava spesso improvvisamente da un concetto all’altro, da una formula alla successiva senza curarsi affatto di spiegare la connessione che le legava. Le sue presentazioni erano nuvole oscure illuminate di tanto in tanto da lampi di puro genio. Dei trenta che si iscrissero all’inizio, io fui l’unico a [...]

+

Maximum Entropy Hadamard Sensing of Sparse and Localized Signals by Valerio Cambareri, Riccardo Rovatti, Gianluca SettiThe quest for optimal sensing matrices is crucial in the design of efficient Compressed Sensing architectures. In this paper we propose a maximum entropy criterion for the design of optimal Hadamard sensing matrices (and similar deterministic ensembles) when the signal being acquired is sparse and non-white. Since the resulting design strategy entails a
[…]

+

geometricloci:
Parametric curves by[R-D]
La mia arte matematica. Queste figure ricordano vecchi merletti, solo che sono ottenute attraverso equazioni.
Enjoy!

+

12:45 AM | Day 1: Sooooo.... school.

Day 1 was not so bad. I like to minimally wah wah wah about the syllabus, because they won't remember anything until the information matters, so we all did some math today.Algebra 2Unit 1 is series and sequences so we went in hot with Eating Grapes.On Monday Angela ate some grapes. On Tuesday shewas hungrier and ate six more grapes than she ate onMonday. Each day that week she ate six more grapesthan the day before. After she had eaten her grapes onFriday she had eaten 100 grapes in all.I read […]

+

12:01 AM | Starting class positive

Every single day since the beginning of school I have stood at my door and high-fived every single learner who has walked into my room. No joke. If I miss one because I was talking to someone, I go back and find them. Well, all except for one learner who gave me a funny look […]

### August 20, 2014

+

Every compact ring is totally disconnected.

+

The Simons Institute for the Theory of Computing at UC Berkeley invites applications for Research Fellowships for the research program on Cryptography that will take place in Summer, 2015. These Fellowships are open to outstanding junior scientists (at most 6 years from PhD by 1 May, 2015). Further details and application instructions can be found […]

+

11:30 PM | Fields Medal 2014

Congratulations to the 2014 Fields Medalists! Every four years, the International Mathematical Union (IMU) awards the Fields Medal to two, three, or four mathematicians under forty, recognizing them for their research and contributions to the discipline. The Fields Medal was … Continue reading →

+

11:16 PM | Right Triangle Altitude Theorem

Today we will learn about Right Triangle Altitude Theorem and use it to derive Pythagorean Theorem.Right Triangle Altitude TheoremWe know that two similar triangles have three pairs of equal angles and three pairs of proportional sides. If someone asks you what is your favourite example of similar triangles, what would you say?For me, it has to be the Right Triangle Altitude Theorem. The theorem is constructed as follows.First, we draw a right triangle $ABC$ ($\angle B$ is the right […]

+

11:00 PM | On This Day in Math - August 21

As for methods I have sought to give them all the rigour that one requires in geometry, so as never to have recourse to the reasons drawn from the generality of algebra. ~Augustin-Louis CauchyThe 233rd day of the year; 233 is the only three digit prime that is also a Fibonacci number. (Are there any four digit ones?)EVENTS1560 The occurrence at the predicted time of a solar eclipse in Copenhagen turned Tycho Brahe toward a life of observational astronomy. *VFR Thony Christie has stated that it […]

+

10:14 PM | To Susie [by Kerrie Mengersen]

[Here is a poem written by my friend Kerrie for the last ISBA cabaret in Cancun, to Susie who could not make it to a Valencia meeting for the first time... Along with a picture of Susie, Alicia and Jennifer taking part in another ISBA cabaret in Knossos, Crete, in 2000.] This is a parody […]

+

9:43 PM | Maths in Dance - Joel and Ana Masacote

Dancers are busy people - and no two are busier than Joel and Ana Masacote, legends in the field of Latin Dance. So, it was really great to get a reply from Ana saying that Joel and she would also love to participate in the "Maths in Dance" project. I realise we are a few weeks past the end of August but this was too good an offer to let slip past. So, who are Joel and Ana Masacote?This husband and wife team is one of the most sought after in salsa/mambo. Respected for their artistry
[…]

+

9:27 PM | Ascending The Eigen - a.k.

In the previous post we covered eigensystems of two by two matrices, being the set of unit eigenvectors vi and eigenvalues λi that satisfy the relation
M × vi = λi × vi
To find the eigenvalues of a matrix M we solved the characteristic equation
|M - λi × I| = 0
Now for a two by two matrix this was a simple quadratic equation that we could solve with the equation we learnt in school. […]

+

We have been studying linear and nonlinear patterns in Prealgebra the last week and a half.The students are all great at creating tables and graphs from those patterns, and most can identify an expression for any figure in the pattern, so I thought that would be a natural introduction to slope and intercepts. We have taken the old patterns and tables and graphs from the last 1.5 weeks and identified the slopes and y-intercepts for each one, and even looked at nonlinear examples. I want students
[…]

+

8:50 PM | Astroboy: Il gatto rosso e altre storie

Il gatto rossoLa prima reazione di uno straniero alla Tokyio del duemila è di stupore di fronte a una strana metropoli che mescola alla rinfusa la civiltà progredita del ventunesimo secolo con le antichità del ventesimo.Passeggiando per Musashino non devi scegliere che strada percorrere. Puoi essere pago del percorrere senza meta le sue vie che ti condurranno in luoghi singolari e se per caso chiedi indicazioni a un passante non te la prendere se questi risponderà gridando. La strada
[…]

+

The Vedic Maths Forum South Africa organized the First Speed Maths Challenge in August 2014. Here are some pictures from the grand event! Post by Vedic Maths Forum South Africa.The Vedic Math Forum India
Worlds Fastest Mental Math System
http://www.vedicmathsindia.org

+

Manjul Bhargava Heartiest Congratulations to Manjul Bhargava for the coveted Field's Medal in Mathematics.Manjul Bhargava, the first Indian-origin mathematician to win the coveted Fields Medal, says the inspiration behind his discoveries in number theory has been the classic works of ancient Indian mathematicians. "Their works contain incredible mathematical discoveries, and were very inspirational to me as a young mathematician. The classic works of Pingala, Hemachandra, and
[…]

+

[This guest post is authored by Matilde Lalin, an Associate Professor in the Département de mathématiques et de statistique at the Université de Montréal. I have lightly edited the text, mostly by adding some HTML formatting. -T.] Mathematicians (and likely other academics!) with small children face some unique challenges when traveling to conferences and workshops. The goal […]