Classical questions of eight-character model

The classic questions of the eight-character model are as follows:

1. Parallel A-shape: In △ABC, D and E are the midpoint of AB and AC respectively, and when DE∥BC, △ADE∽△ABC. At this time, DE is the median line of △ABC, and DE=1/2BC. This question mainly examines the nature of parallel lines and similar triangles's judgment.

2. parallel x (parallel figure 8): also in △ABC, DE∥BC, at this time △ADE∽△ACB. This type of question also examines the nature of parallel lines and similar triangles's judgment.

3. proving the relationship between sum and difference of line segments: this kind of problem usually needs to prove the relationship between two line segments that are not on the same line, for example, proving AC=AE+CD. At this time, we can consider using the method of "learn from each other's strengths" to prove it.

The above are some classic questions of the eight-character model, which occupy an important position in mathematics. In order to master these questions skillfully, a lot of practice and thinking are needed. Please note that these questions are based on some basic mathematical knowledge, such as the nature of parallel lines and the judgment of similar triangles.

Therefore, before learning these questions, you need to make sure that you have mastered these basic knowledge. At the same time, in order to better understand and master these questions, we can try to solve these problems from different angles and ideas, which is helpful to cultivate mathematical thinking and problem-solving ability.

definition of eight-character model

eight-character model is a computer program that calculates an output through two inputs. These two inputs are usually called "the left leg of the eight-character model" and "the trunk of the eight-character model", while the output is called "the right leg of the eight-character model".

the eight-character model is a very simple model, which is usually used to calculate the relationship between two variables. For example, it can be used to calculate the sum-difference product quotient between two numbers, or to calculate the number of days between two dates.