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Open the textbook, rotate or translate?
In the three-dimensional angle, of course, the spine is the axis of rotation. In the two-dimensional angle, it is neither translation nor rotation
Is opening and closing doors a rotating phenomenon
It's rotation
In the plane, the transformation of a figure rotating around point O is called rotation, point O is called rotation center, and the rotation angle is called rotation angle
Opening and closing doors also revolve around a point, which is a phenomenon of rotation
How many degrees can the door of the classroom rotate?
The height of the door is about (20.2) decimeters, the width of the door is about (8.6) decimeters, (draw the plan). Can you find out the floor area after opening the door?
4. The front and back doors of the classroom open, covering an area of about () square meters
In fact, this is a problem of fan-shaped area. In theory, the door of a classroom can rotate 180 degrees, that is, the door can rotate around an axis of 20.2 decimeters. It is meaningless to simply calculate the floor area. In fact, the door is three-dimensional, so it should be counted as occupying space. The floor area has nothing to do with the height of the door
Open the door, is it translation or rotation?
If it's a glass door, it's translation
After the figure is translated, the position relation of the corresponding line segment is
The translated graph is parallel (or on the same line) and equal to the corresponding line segment of the original graph
Moving a figure along a certain direction in a plane for a certain distance is called translation. The following statement about translation is correct: a-plane
Moving a figure along a certain direction in a plane for a certain distance is called translation
A translation does not change the size of the figure, only the shape of the figure
B translation does not change the position of the figure, only changes the size of the figure
C translation does not change the shape of the figure, only changes the size of the figure
D translation does not change the size and shape of the figure, only changes the position of the figure
D
After translation, each point on the graph moves in the same direction
After translation, each point on the graph moves the same distance in the same direction
Translation: an object or figure moves along () for a certain distance in the same plane without any change in direction. This phenomenon is called translation
Straight line direction
Translation of graphics
1. If a △ ABC is shifted to the right by 0.8 cm, then a point D on edge AB whose distance from point a is 0.3 cm is shifted to the right____
2. Put the chess pieces into the "t" pattern as shown in the figure
(1) Translate the 100th "t" so that there are as many overlapping pieces as possible between the 100th "t" and the 770th "t", then the non overlapping pieces are shared_____ individual
What about the first question
1:0.8cm 2:98
What is a regular polygon? What conditions should it meet?
A polygon with equal sides and angles is called a regular polygon. Polygon: the center of a regular polygon whose number of sides is greater than or equal to 3. The center of the circumscribed circle of a regular polygon is called the center of the regular polygon. The length of the line between the center and the vertex of the regular polygon is called the radius. The distance between the center and the edge is called the edge center distance
RELATED INFORMATIONS
- 1. When drawing with ruler and compasses, move an angle (not translation), and the two sides of the angle are not parallel,
- 2. Is parallelogram an axisymmetric figure
- 3. Are equilateral triangles and squares axisymmetric figures? How many axes do they have
- 4. What's the difference between translation and distance
- 5. Which geometric bodies in our life can be obtained by the rotation of plane figure? What plane figure can they be obtained by rotation? Give an example
- 6. Uncle Zhang is driving on a straight road. What is the movement of the steering wheel Translation or rotation
- 7. In life, we see many objects moving. How do they move?
- 8. Solve right and wrong math problems 1. If two numbers are composite numbers, their common factor can not be only 1. (right) (wrong)? 2. Number a is a multiple of number B, and the greatest common factor of these two numbers is 1. (right) (wrong)? The greatest common factor of 3.15, 45 and 60 is 15. (right) (wrong)?
- 9. What is the phenomenon of elevator up and down movement and what is the movement of windmill rotation
- 10. The up and down movement of elevator is () phenomenon, the rotation of windmill is () phenomenon?
- 11. We know the line y = - 3 / 2x-1. (1) how to translate the line along the X axis to make it pass through the origin? (2) How to translate the line along the Y axis to make it pass (- 2,4)?
- 12. After translating the vector a = (3, - 2) according to the vector (1,1), we get the vector B, then | B|=
- 13. If the image of quadratic function y = X2 is translated according to vector a, the image obtained has only one common point (3,1) with the image of linear function y = 2x-5, then vector a = () A. （2，0）B. （2，1）C. （3，0）D. （3，1）
- 14. What are the common biological characteristics
- 15. How long does the earth rotate
- 16. Which of the following patterns are obtained by rotation?
- 17. What things in life use space technology
- 18. After a figure is enlarged or reduced, the shape of the figure must have changed due to the change of all sides
- 19. In the northern hemisphere of the earth, some people use shadow to distinguish the direction: as shown in Figure 8, a straight rod is inserted vertically at o point on the horizontal ground. Around noon, point tracing method is used to draw the running track of the top of the rod's shadow on the ground, and the point a nearest to o point is found on the track, then the direction indicated by OA is__________ (select "East", "West", "south" and "North")
- 20. How to draw the rotation of the figure