For the drawing of three-dimensional shapes, why not use geometric artboards to make them? Because the geometric artboard was born for flat geometry from the beginning, although it is possible to indirectly simulate the simple animation of spatial graphics, the visual effects and expression ability are really incomparable with ggb. Crucially, geometry artboards began to be officially no longer maintained and updated in 2015.
This article explores the following high school stereo geometry problems:
The topic is a little difficult.
Ggb drawing is very simple, just draw according to the theme.
The static effects are as follows:
The dynamic effects are as follows:
Question 1: Why is there a cone?
Because the two corners with N as the apex are equal!
So the point Q is on the cone!
Question 2: Why is the trajectory of point Q a parabola?
Here's why:
That is, there are conditions for parallel lines here!
Reflection 1: Can this conic curve be made with ggb? It's easy!
For example, the effect made by the author: (click to open)
The process of forming a conic curve
What shapes can I get from a planar truncated cone?
Visualization of the cutting of the cone (with instructions attached)
The volume of the cone is one-third of the volume of a cylinder of equal bottom height
Case 36: Graphical presentation of the uniform definition of a conic curve
The shortest path for ants to crawl on cylinders and cones
2020 Jiangsu New College Entrance Examination a demonstration of the folding cone curve problem
Geogebra is exploring the application of common features of conic curves
Reflection 2: What about Dandrin's double ball?
The author also has such a tutorial.
Geogebra Advanced 104: Classic Case Of the Famous Dandling Double Ball Model (Video and Text Tutorial)
Two models of the Dandrin bisphere model: get the ellipse
Introduction to the production of the Dandeling double ball model