Because we’re so in love with technology, and because we’re so short of things to do and, mainly, because we’re so, so stupid, we’ve agreed to give a LunchMaths/MUMS talk via Zoom this Friday.

The details are below, and this link is supposed to work. Attempt to enter at your own risk.

**UPDATE (24/08) **

The video of the talk has been uploaded and can be viewed on YouTube and/or on this post.

Well I’m meant to be “teaching” at that time, but since I pre-record all my lessons I can probably tune in…

Thanks. I’ll tune in too. Looks fun.

me 3.

12 pm at which timezone?

AEST – Australian Eastern Standard Time. i tried to get the organisers to shift it so it’d be prime time in the US, but they seemed to think I was nuts.

I think you meant that you wanted us to have it pushed back into September 😛

Yes, September 2027.

Alas, I won’t be able to make that. Any chance it will be recorded?

One can only hope not. In fact, I think it may be recorded, but, even ignoring questions of intrinsic worth, my sense is zoom recordings don’t work that well.

The subtle magnet messaging in the background was a nice touch.

Thank you for noticing!

Marti,

I take it you were not heckled and there were no dll issues with the zoom application .

BTW Did any one point out a root of the quintic in real time?

Steve R

Hi, Steve. I’m never heckled. Well, there was that one time an MAV president insisted on shooting themselves in the foot, but that was a special case. People who think I’m screwy, and there’s plenty who do, think the best strategy is to ignore me.

With the quintic, I pointed it out. I’m sure some would have seen the point already, but it was difficult to get real-time feedback during the talk.

How did it go?

Not sure. I’m not the one to ask.

It went very well. Chatty, maths, education, whacks, all good. Very nicely placed magnets behind marty. Zoom meetings are a bit shit in terms of easy interaction, but that’s not marty’s fault.

A couple of follow-up things maybe:

* marty, you said that 2/3 of the topics in the “it’s all crap” talk (i forget the title, but the one with the many many topics on the screen, and the (massive) audience shouts out VCAA” or “MAV” or “CAS” and you click that and expound) have never been seen – i’d be interested if you could take any of those and expound a little here on this blog. Or put up that many-topics image and get us readers to vote???

* and marty, if you could take a deep breath and explain why that line of reasoning to prove 2^0 = 1 by 2^(3 – 3) = 2^3 / 2^3 = 1 is no good? why is it a matter of definition not proof?

* and you should not feel that your work in improving and identifying problems in maths and maths teaching has had no effect. Sure, the situation is not solved, but it’s slightly less shit for the light you’ve thrown. And you’ve made people laugh along the way – I often yell across the room at my partner, “hey, listen to what that marty maths guy wrote this time!”. (the film “A Wonderful Life” springs to mind. And there’s some quote – I can’t find it or remember it – something like “The situation is hopeless. But we must carry on”.) And your simple thing about Know your subject, Know your students, Care about both is pretty good stuff.

good on ya marty. keep whackin.

Thanks, rob, and nice of you to say. It was a very weird thing to do. I’lll reply on your points later.

Hi, rob. Briefly in reply to your questions:

1. The lecture you referred to is called Same Sermon, New Jokes. I do have thoughts for putting it in some form on this blog. Just not quite sure how, or when I’ll get the time.

2. SRK, has replied in terms of the index laws. I know this confuses lots of teachers, not least because most of the textbooks screw it up. I may put up a separate post on this.

3. As to whether what I do is useless or not, thanks for your comments. I may also put up a post on this. In yesterday’s talk what I was specifically referring to as useless was the popularisation I’ve done. The value or not of my whacking is a separate issue.

Rob, my understanding is that initially 2^x is defined only when x is a positive integer, since we think of 2^x as the product of x occurrences of 2. Hence 2^(3 – 3) is undefined, so that “proof” is nonsense.

If we want to attach a meaning to 2^x, where x is a non-positive integer (never mind rationals and irrationals), then we can no longer lean on the idea of repeated multiplication. So instead we just *define* 2^0 = 1, 2^(-x) = 1/(2^x), and so on. The motivation behind these definitions is so that the index laws true when x is a positive integer will also be true when x is any real number, but this is a matter of convenience and simplicity, not logical consistency.

Thanks, SRK. That’s it. In summary, we can’t have an index law for before we know what means.

Hi,

I think the arguement for and against a definition for a^b as a and b approach zero have also been mentioned in a previous thread on Woo and 0/0.

As there it depends on your context as Marti mentions you need a definition eg you might want the binomial theorem coefficients or the derivative power rule to validate or be counting in combinatorics .

Wikapaedia is fairly generous allowing the arguement of the exponent b to be defined for any Real With extensions to Complex numbers

https://en.m.wikipedia.org/wiki/Exponential_function

Another opinion is given here which I have some reservations

https://www.math.toronto.edu/mathnet/questionCorner/powerof0.html

Steve R

I agree that there are many instances where mathematical problems are stated in contexts that are not necessary, and sometimes the contexts are downright distracting from the main point. Even worse, sometimes they are thinly veiled attempts to make statements about society.

Often such questions require knowledge of the context. Halsey (2018, p. 32) refers to a NAPLAN question about what you might see at a “busy train station”, and many Australian students will have no experience of a busy train station.

Framing a question on applied mathematics (which includes statistics) requires more than a superficial context.

Reference

Halsey, J. (2018). Independent review into regional rural and remote education—Final report. Canberra, Australia: Commonwealth of Australia.

Misinterpreting train stations is the least of the issues with NAPLAN.