Yet another GeoGebra

18 January , 2011

Several versions of GeoGebra are planned launched, and you can try some of them now in their beta stages. I have mentioned GeoGebra(prim) earlier on my Norwegian blog – a scaled down, simplified version intended for primary school use. I also suspect there’s a SMARTboard version in the making (although you can make your own version for the SMARTboard by making points and text much larger!) Yet another version is what will become GeoGebra 5.0 (ok, I know we haven’t reached 4.0 yet, but let’s not get into details…), GeoGebra 3D.

A lot seems familiar at first glance, but a couple of new entries can be seen on the toolbar.
CAS is mentioned in the Norwegian curriculum, and up until now, the only free and rather easy alternative is wxMaxima.


At least two new choices of “mode” has turned up. In the picture above you see the CAS mode. This is a part of GeoGebra that can be used for things like solving equations algebraically and simplifying expressions. I solved a quadratic in the screenshot, and I had no idea about the syntax beforehand. It turned out it was similar to most other CAS’s , for instance, wxMaxima, Texas Instruments-calculators and others.


Not many 3D software systems intended for school use exists to my knowledge. One alternative is Google Sketchup. One option in Google Sketchup is to “drag” areas upward to turn them into prisms. This is also an option in GeoGebra 3D, as you can see in the screenshot.
You can download the test version with 3D and CAS here:


Battle of the traditions…

25 November , 2010

A few days ago, this comic appeared in my Google Reader: OK, this is not too difficult when you know who Kenny Baker is (and who doesn’t?!). Click that previous link before you read further.

I then did the calculations by hand, as seen in the first picture (yes, it looks horrible, just like mathematical work should).

I figured I should check my answer, and brought out my TI-89. Not a tool I use too often, as wxMaxima and GeoGebra fulfill all my needs, but it was “nice” to see it again.

Punching in the exercise I got the correct answer there too, shown in the calculator shot.

Now, first of all, nice going on making this exercise Spiked math! Finding proper integration limits so that integrating C-3P0 turns into R2-D2 is not trivial.

Second, it struck me how different even straight forward exercises like these are when using two different means of solving. One can argue using a calculator is less work for the brain, but I can’t recall one instance in the handwritten version, where I actually had to stop to think. It was all memorized rules of calculus and algebra, rote work.

Using a CAS like the TI-89 (now replaced by the TI Titanium, and later the TI n-spire), there was still not much work for the brain involved. The only parts where you (or rather, I) would stop to think was wether the syntax of the input line was “expression, variable, lower limit, upper limit” or “expresseion, lower limit, upper limit, variable”. Logically enough, you should tell someone (anyone!) what dummy variable is involved in the calculations before applying the limits of integration.

Either way, solving the problem felt good because it was Star Wars related. The one who learned anything at all from this, was the one who devised the problem in the first place.

And perhaps Kenny Baker got a giggle out of it, too.

Windows 7: The calculator has a lot of new features. | Ask The Admin

12 February , 2010

Windows 7: The calculator has a lot of new features. | Ask The Admin.

Cool, I wasn’t aware of this, but come to think of it, the calculator in Windows hasn’t really gone through many stages of development. I guess there’s no real point in putting a CAS/DGS inside Windows by default, since excellent freewares already are being domesticated in schools and higher education, but you never know. What kind of mathematics calculating systems would we see built into the OS? My gut feeling is I ‘d still want my GeoGebra fix.

Let Live Search Do Your Algebra

13 April , 2009

Great idea from : Let Live Search do your algebra. I guess most of you are familiar with the fact that google search (even the search bar in Firefox) can do simple calculations and unit conversions. Microsoft’s latest effort goes to eleven though. It is capable of solving simple algebra problems. With symbols. So it’s one point for microsoft. Firefox and Google had thousands of points from before, but this means they are catching up 🙂