Central theme: basic plane graphics

I. Sub-theme 1: Line segment

1. Definition: A line segment is a straight line with two endpoints and between them.

2. Attribute: The line segment is straight and has two endpoints, so the length can be measured.

3. Representation method: it is represented by letters at both ends, such as line segment AB.

Two. Sub-theme 2: Corner

1. Definition: An angle is a graph formed by the intersection of two rays or line segments on the same line.

2. Nature: The angle has a vertex and two sides, and the size can be measured.

3. Representation method: represented by vertex letters, such as AOB.

Three. Sub-theme 3: Triangle

1. Definition: A triangle is a figure consisting of three end-to-end line segments.

2. Nature: A triangle has three sides and three angles and is stable.

3. Representation method: it is represented by letters with three vertices, such as triangle ABC.

Four. Sub-theme 4: Quadrilateral

1, definition: A quadrilateral is a figure composed of four line segments connected end to end.

2. Properties: Quadrilateral has four sides and four corners, which are divided into convex quadrilateral and concave quadrilateral.

3. Representation method: it is represented by letters of the endpoints of four sides, such as quadrilateral ABCD.

The production of mind maps can be considered from the following aspects:

1, Definition: First, we need to make clear the basic definition and characteristics of graphics. For example, what is the definition, what basic elements it contains, and how these elements form a graph.

2. Attributes: Analyze the attributes of the graph, including shape, size, angle, number of sides, etc. These properties determine the characteristics of graphics in geometry, algebra or space.

3. Classification: Graphics can be classified according to attributes. For example, triangles can be divided into equilateral triangles, isosceles triangles and right triangles.

4. Application: Consider the application scenarios of graphics in real life. For example, a circle can be applied to the design of various containers and tools, and a rectangle can be applied to the design of buildings and furniture.

5. Formulas and theorems: For some common figures, such as triangles and rectangles, we can list their related formulas and theorems, such as Pythagorean theorem and the properties of parallelograms. These formulas and theorems can help us better understand and apply graphics.