Geometry with GeoGebra3D
Revista de Didactica de las Mathematicas 2015
Table of Contents
- Introduction
- Sketch of a House
- Spatial Geometry
- Net of a Dodecahedron
- Conics - Proof by Dandelin
- Analytic Geometry
- Interrsection of Line and Plane
- Spherical coordinates
- Decriptive Geometry
- Central projection of a Cube - Perspective
- Projection of a Sphere - Central Projection
Sketch of a House
Choose different views: [br][list][*]view towards xOy plane, [/*][*]view towards xOz plane[/*][*]view towards yOz plane[/*][/list][br]Rotate the view![br][br]Move any point of the base rectangle.
Net of a Dodecahedron
Fold the net of the dodecahedron
Andreas Lindner
Interrsection of Line and Plane
[b]Example[/b][br]Intersect the line g: [math]X = \left( \begin{array}{c} 0\\ 1\\2 \end{array} \right) + t\cdot \left( \begin{array}{c} -1\\ -2\\1 \end{array} \right) [/math] and the plane ε: x + y + z = 1 und calculate the coordinates of the intercept point S.[br][br][b]Exercise[/b][br]Change the plane to ε: x + y + z = 2 and observe the consequences.[br]What are the coordinates of the intercept point now?
Interrsection of Line and Plane
Central projection of a Cube - Perspective
[b]Exercise[/b][br]Change your position with right mouse button and view the construction from different sides.[br][list][br][*]Move the position of the [color=#1551b5]center of the projection[/color] in horizontal and vertical direction.[br][*]Show the horizontal plane and auxiliary lines by clicking on the check boxes.[br][*]Enlarge oder shorten the sphere by moving point B.[br][*]Choose[i] front elevation[/i] (upright projection) in the style bar.[br][*]The position of the image plane can moved with point P.[br][/list]
Andreas Lindner