Saturday, December 19, 2015

Factoring tricks

As previously mentioned, I've been working with a non-profit that runs after school tutoring programs helping with the math side. Part of the problem is that the program leans toward the humanities side and some of the tutors are not at all comfortable with math.

I've been throwing together some short, smart-phone friendly videos for this target audience.

Everything here is modular. I dictated the scripts to dragon, created SVG graphics in Inkscape, put together the slide in Impress and PowerPoint, recorded the audio in Audacity and did the final edit in KDENlive. It's quick, not slick, but it is set up in a way that any given element can easily be changed.

Any feedback is appreciated.


  1. Say that primes are defined to start at 2 and after talking about primes and composites say that 1 is neither.

    For factor trees, you can start with any two factors and then partition them out rather than having to start with the smallest prime. For example, for 100 you might go 100 = 10 x 10. And the for the 10's, 10 = 2 x 5 which are both primes. It helps if the lowest prime factor is a large number and it's easy to see a non-prime factorisation.

    You could perhaps add that every composite number ("remember those are the non-prime numbers") has a prime factorisation.

    1. I was thinking that most of the viewers would see the factor video first {} so I didn't want to spend too much time reviewing the fundamental theorem.

      I generally lean toward the start-with-the-smallest because it groups the factors together in the proper order. That said, the just-keep-going-till-you-hit-primes has fewer rules and may seem more natural.