GeoGebra 4.0 Essentials Series

My apologies. I am quite busy for the past two weeks, and looks like I am going to be busy until the first week of March.  Anyway, for those who had not visited Mathematics and Multimedia recently, the GeoGebra Essentials Series had already been updated to version 4.0. 

The first 10 tutorials in the GeoGebra Intermediate Tutorial Series were also updated last month.  I hope this will help those who want to learn the new version of GeoGebra. 

I am going to resume the revision next week.

Error in Posting and New Blog Contributor

Hi guys. I have been trying to post applets since Saturday, but no luck so far (I always get an error). Maybe it's a GeoGebra bug. I'll email Michael Borcherds (Lead Developer) later.

By the way, I am welcoming another  new contributor of this blog, William Emeny of Great Maths Teaching Ideas. William Emeny is also a great GeoGebra fan.

Erlina Ronda, one of the contributors of this blog, has a new URL and a new name for her blog. She has named here new blog Teaching K-12 Mathematics.

All other GeoGebra users are welcome to contribute here. If you are interested, contact me at mathandmultimedia@gmail.com

St. Valentin

Happy Valentines Everyone. Here's an excellent applet created with GeoGebra.

This is a Java Applet created using GeoGebra from www.geogebra.org - it looks like you don't have Java installed, please go to www.java.com

Courtesy of Daniel Mentrard. Ggb file can be downloaded here.

Conjectures and Proof in GeoGebra

Sorry, the GeoGebra Applet could not be started. Please make sure that Java 1.4.2 (or later) is installed and active in your browser (Click here to install Java now)

Circumcircle and Incircle of a Triangle

This GeoGebra worksheet below shows that in a triangle, you can always create an incircle (a circle inside the triangle tangent to the tree sides) and a circumcircle (circle passing through the three vertices).

Drag the vertices of the triangle and observe what happens.



You can download the ggb file here and the tutorial how to construct it here.

Geometric representation of the sum of two radicals

This activity is part of the lesson on adding radicals posted at Mathematics for Teaching.

How to construct the figure:

Use the regular polygon tool. Click on two points (endpoints of the diagonal of 2 by 1 unit square in the grid). From then on just click on the diagonals each time to generate the squares.

To type the radical, use the text tool, click anywhere on the grid, check latex in the dialogue window and type \sqrt{5} and you're done.

To change the color, right click on the figure, click color, choose and you're done.

When you are ready click on the file menu and choose new. This will give you a brand new grid to practice constructing the figure.





















Sorry, the GeoGebra Applet could not be started. Please make sure that Java 1.4.2 (or later) is installed and active in your browser (Click here to install Java now)