1. Mathematical writing with GeoGebra Anders Sanne Morten Misfeldt

2. A discussion on a mountain in Iceland… How to increase the use of GeoGebra for producing mathematical text. – What is the role of GeoGebra in the production of documents? Something that you write about A good machine to produce illustrations – What could it be? Interactive illustrations Answers to mathematical assignments delivered in GeoGebra

3. Why consider text GeoGebra is strong on different mathematical representations Text is the archetypical ”discursive” – or linear – representation.

4. Semiotic representations: Duval Mathematical activity constist of transformations of semiotic representations Register: ”space of semiotic representation” (2dplot, algebra, natural language) Treatment: transformations inside a register Conversion: transformations that change register but maintain conceptual reference

5. Examples The unit circle in different registers x 2 +y 2 =1”the unit circle” Treatment 3x+9=0 => x=-3 Conversion 2x+1 =y can be shown as

6. Four main types of registers DiscursiveNon discursive MultifunctionalEx: Natural language Ex: Geometric figures monofunctionalEx: algebraEx: Cartesian graphs

7. Why text (2) GeoGebra is strong in its support for non discursive registers Less strong with Discursive – Problem with discursive expansion Proofs Explanations Narrations All sorts of reasoning activities

8. Two approaches to text in GeoGebra Embed GeoGebra in word processing. – Google gadget and save as webpage Include text processing and formulas in GeoGebra – The improved text box – A ”caption” or text view? – Dynamic use of txt

9. A text view could be here

10. Producing mathematical documents Integrated text view could make it possible to produce simple printable mathematical documents. Using only GeoGebra for math assignments and test situations Avoid cut and paste Strong integration with the other views in GeoGebra

11. Typical assignments in K-12 ed. With a text view GeoGebra could produce solutions to typical K-12 assignments – A figure – Some calculations – Text describing the problem and solution

12. Documentation of GeoGebra based reasoning Arguing for reasoning strategies and procedures Describing observations A complement to the construction protocol (there is a caption field in the new construction protocol) Enhancing (mathematical) literacy

13. Conclusion Writing should of course be considered when using GeoGebra for teaching mathematics This can be done by embedding GeoGebra applets in a text domain But creating a simple text view could supplement this approach