## Friday, November 13, 2015

### Math Links for Week Ending Nov. 13, 2015

Seriously, my love fest with Desmos continues. Check this out. You may have seen images like the one of the propellor seen here before where the actual propellor looks like it exploded. Well thanks to this Desmos sketch we now know exactly it happens. It's due to the way the digital shutter works on a camera. It sweeps from one side to the other (or top to bottom) tracing out what ever is moving. There is definitely some advance function and polar coordinate action happening on this one. And you could probably definitely connect some related rates with calculus too. Make sure you look at the actual Desmos sketch too. You can adjust sliders for the speed of the propellor and shutter and there are other examples on the page below that shows what happens with different shaped propellors.
Curriculum Tags: MHF4U, MCV4U
https://imgur.com/gallery/RG7Kd

Over the last couple of years @marybourassa has been giving her daily routine for her grade 10 applied course. This semester she is doing the same with her Grade 10 academic course and along the way she is creating new stuff and using old stuff. Like this matching activity for trig and similar triangles. She is at Day 45 right now. Half way through the semester. Check out all of her grade 10 academic posts here.
Curriculum Tags: MPM2D
http://marybourassa.blogspot.ca/2015/11/mpm2d-day-42-similar-triangles-and-trig.html

Here is a neat couple of posts from @jreulbach that introduce the idea of logarithms by starting with the zombie apocalypse and creates a need to have a logarithm. Then it follows up with a second post that does the actual introduction to logs. And of course it uses, you guessed it, Desmos.
Curriculum Tags: MHF4U
http://ispeakmath.org/2015/11/07/creating-a-need-for-logarithms-with-zombies/
http://ispeakmath.org/2015/11/07/inverse-functions-and-logarithms/

Not everything @marybourassa is doing is about grade 10 advance math. In this post she has a Desmos Activity Builder activity on logarithmic transformations. All hail Desmos
Curriculum Tags: MHF4U
http://marybourassa.blogspot.ca/2015/11/log-transformations-desmos-activity.html

And the Desmos activities keep coming. Here's another post from @jreulbach. This time on transformations and includes both paper and pencil and four separate Desmos Activity Builder activities.
Curriculum Tags: MPM2D, MCR3U, MCF3M
http://ispeakmath.org/2015/10/28/algebra-2-transformations-unit-starring-desmos-teacher-activities/

Another example of the #MTBoS in action. @fawnpnguyen visualpatterns.org is a legitimate hit and based on that @samjshah had his students create funky 3D patterns with cubes to connect to arithmetic and geometric series and sequences.
Curriculum Tags: MCR3U
http://samjshah.com/2015/11/05/playing-with-blocks-three-dimensional-visual-sequences/

And another one from @samjshah starts out seeming very innocent: "At 3:00, the hour and minute hands on a clock form a right angle. What is the next time that happens?" Then he then goes on to solve it using the dot product of vectors using functions over time. Nice
Curriculum Tags: MCV4U
http://samjshah.com/2015/11/06/clock-puzzle/

I love how @paul_math takes the idea of quotes that keep you going as a teacher and then shows this quote
"Put bluntly, learning based purely on procedural methods has little meaning or long term retention for most students, and does not facilitate the depth of understanding needed to use math for any worthwhile endeavor outside (or inside) of school. Even more bluntly, its boring, demeaning, and encourages the all-too-prevalent perception that mathematics is difficult, useless and unintelligible."
And then he brings it around to talking about the OAME. Nicely done
Curriculum Tags: All
http://mathsoxlearner.blogspot.ca/2015/10/my-comfort-quote-im-pretty-sure-im-not.html

And kind of along the lines of that quote is a neat math fight going on on @ddmeyer 's blog. Pick a side: Understanding Math vs Explaining Answers. Interesting to see how divided some are on this.
Curriculum Tags: All
http://blog.mrmeyer.com/2015/understanding-math-v-explaining-answers/

It is always good to try to find connections for all our students and some of our female students are dreamers about weddings. So why not give them some fun graphs about wedding planning?
Curriculum Tags: Gr7, Gr8
https://www.youtube.com/watch?v=-qSN_hzNafc

Some fun math in a 5 minute package from @standupmaths. I love the tiny proof that all roots of 2 are rational and how that is connected to Fermat's Last Theorem. And then the crazy sequence proof dealing with primes. Though these are specific topics I think they could connect to just about any math class.
Curriculum Tags: All
https://www.youtube.com/watch?v=W1OkVkq2vFM

I'm always looking for interesting data to analyze. Here is a fun graph on the popularity of actor Shia LaBeouf. Have your kids do some inferencing on this
Curriculum Tags: Gr7, Gr8

A quick one from @marybourassa. Can't get enough Pythagorean humour
Curriculum Tags: Gr8, MPM1D, MFM1P, MPM2P, MPM2D
http://marybourassa.blogspot.ca/2015/10/mpm2d-day-24-cycle-1-review.html