## Working with Geogebra Basics

• Working with Geogebra Introduction

Welcome all of you 😊

### With this introduction you’ll get basic informations about the use and the possibles of GeoGebra.

We work with Geogebra classic 5. The language will be set into English.

You can watch the file Geog_SetLanguage.mp4 to learn how to change the language.

#1      Set the language to English.

Basics for functions

You can make all these tasks if you  already now how to work with Geogebra, make sure you’re partner also understands! So the most important goal here is to get on the same level. If you both don’t know how to fulfil the tasks you can watch the video. You still don’t know? Ask a teacher. Have fun.

#2 Make a graph of f(x)= x² -3x+2. Save the file as task2.ggb

This was a rather simple function and you wouldn’t need Geogebra to plot it. And you could have guessed it would become more interesting if we introduce a parameter p in the function.

We will discover the function: fp(x)= x² + p x +2

#3 Make a graph of  fp(x)= x² + p x +2. Create a slidebar for -5≤p≤5. Save the file as task3.ggb

(If you don’t succeed you can watch Geog_ParameterFunction.mp4)

If you change the parameter you’ll discover the top will move. The top seems to be located like: Ytop= - x² +2

#4 Plot Ytop= - x² +2 in the previous file. Slide the bar and agree that

Ytop= - x² +2. could be right. Save the file as task4.ggb

(If you don’t succeed you can watch Geog_YtopParameter.mp4)

Of course we want to be sure that our discovery is correct. So….what do we know about tops? The derived function f'(x) should be 0. If you solve that equation you can conclude that p=-2x. Substitute p=-2x in fp(x)= x² + p x +2 and you proved your discovery.

#5 Write down the prove that Ytop= - x² +2. You can write on paper.

Basics for geometry

So in this paragraph you’re going to create some nice figures. Lines, rectangles, triangles, parallel lines, angle-bisectors and many more.

We don’t need the algebra-window and we don’t need the fancy lined background and axes for geometry.

Watch the video Geog_GeometrySheet.mp4

#6 Create a geometry-sheet without axes and lined background.

#7 Draw a circle. Create a triangle on the circle. Save the file as task7.ggb

(If you don’t succeed you can watch Geog_TriangleOnCircle.mp4)

#8 Draw the three angle bisectors in the triangle. If you change the triangle you can see that the angle bisectors still intersect in one point. You can animate the triangle so it moves automatically. Save the file as task8.ggb

(If you don’t succeed you can watch Geog_TriangleAnimation.mp4)

Geogebra has also a nice option to create regular polygons without a lot of work.

#9 Create a triangle with an angel of 90°.  Create an regular hexagon on each side of the triangle. Save the file as task9.ggb

(If you don’t succeed you can watch Geog_HexagonOnTriangle.mp4)

Yellow and blue makes green, doesn’t it?

#10  Measure the area of the three hexagons. What did you discover? Save the file as task10.ggb

(If you don’t succeed you can watch Geog_HexagonOnTriangleArea.mp4)

# The Dutch team wishes you a lot of fun practicing GeoGebra.

• #### If you have any questions or something is unclear, here is room to ask questions.

##### Vasiliki Kooukouraki- Greece

I tried to follow all the videos. Math is a bit confusing at times but with practice comes perfect, right? I will practice more to become well prepared for The Netherlands

##### Athena Athanasaki - Greece

All the videos were very helpful in order to better understand how to properly use GeoGebra. I propably need more practice but I will struggle to learn everything before going to the Netherlands!

##### Spyros Eirinakis-Greece

The videos helped me a lot.I will practise more to be ready for when we come in the Netherlands.

##### Sara Schaffer;Germany

The videos were very helpful to understand working with GeoGebra. I think I got everything quite well, but I will practice some more to be well prepared when we come to the Netherlands.

##### Maximilian Bill-Germany

These videos were really helpful for me to orient myself on GeoGebra, but furthermore I´ll have to practice. Hope I´ll get it until we´re going to the Netherlands.

##### Lena Gampe - Germany

I also think that the videos are really helpful to understand the various options you get with Geogebra. I’m excited to learn more about it in the Netherlands!

##### Lisa Feuchter-Germany

The videos are great to understand how to work with Geogebra. I watched them several times and I hope that I´m now well prepared for the next week.

##### Paula Engel-Germany

The videos are easy to understand and I think that I'm well prepared for working with GeoGebra. I´m looking forward to the next week!