What are the skills for solving the problems in the first year of junior high school?

I didn't have much contact with the moving points in the second year of junior high school, and the types of moving points in the third year of junior high school were relatively complete.

1.Use graphs to think of triangle congruence, similarity, and trigonometric functions.

2.Analyze the problem and understand how many moving points there are, the distance of the moving point, and the speed (how to move the moving point) 3Combine graphs and problems to derive known or indirect data.

4.Discuss each possible situation and list each possible situation without missing it.

5.The moving point is generally the finale question in the high school entrance examination (at least in Hebei), the steps are not important, the important thing is the idea.

6.There are generally several questions in the moving point class, and most of the previous questions are prompts for the latter question, just like the geometry ** class questions, if the later questions are difficult, you can reverse the past and look at the conclusion of the previous questions.

That's all, the teacher talked about it before the high school entrance examination, and now I have forgotten it, so let's add it when I think about it.

1)3-t=2tt=1

2) Do CE perpendicular to AB rectangle, ADCE area of a certain triangle, QDC and EPC area sum must also be QAPC=ADCE-(QDC+EPC), so the QAPC area must be set at 6

3) Not because when t takes 6 it is.

Right-angled triangle.

But t's. Value range.

It is less than or equal to 3 so it cannot.

Accurately grasp the tips of the initial linkage, and do not control the semi-linkage point well, which will lead to direct failure in the exam.

The skills for solving the problem in the first year of the first year are:The key to solving the problem of moving points is to grasp the moving point, and we must turn the moving point into static. Look for the breaking point.

The length of the edge, the velocity of the moving point, the angle, and the energy of the given graph can establish an equal algebraic relationship, etc., and establish the equivalent algebraic formula sought.

By simplifying the isometric algebraic formula, the unknowns are found. The main idea is to set the point problem.

Number line effect. 1. The number axis can vividly represent the number, and the points on the horizontal number axis correspond to the real numbers one-to-one, that is, each real number can be represented by a point on the number axis.

2. Compare the size of real numbers, with 0 as the center, the number on the right is larger than the number on the left.

3. Imaginary numbers. It can also be represented by a longitudinal number axis perpendicular to the transverse number axis and the same origin, so that the complex number plane with the transverse number axis is formed.

4. Two number axes perpendicular to each other and with the same origin can form a plane Cartesian coordinate system.

The techniques for solving math moving point problems in the second year of junior high school are as follows:

1. Guess the distance between the two points of the rock sail on the number axis, that is, the absolute value of the coordinate difference corresponding to these two points, that is, the difference between the number on the right and the number on the left. That is, the distance between two points on the number axis = the number represented by the right point - the number represented by the left point.

2. When the point moves on the number axis, since the right direction of the number axis is positive, the speed of the right movement of the hail is regarded as positive velocity, and the speed of the movement is regarded as negative velocity. In this way, the coordinates of the point after the movement can be directly obtained by adding the movement distance of the point on the basis of the pure point of the jujube. That is, the number represented by a point is a, and the number represented by moving b units to the left is a-b; The number represented by moving b units to the right is a+b.

3. The number axis is the product of the combination of numbers and shapes, and the analysis of the movement of points on the number axis should be combined with the graph for analysis, and the path formed by the movement of the points on the number axis can be regarded as the sum and difference relationship of the upper section of the number axis.

What is a moving point problem

The moving point problem is to take the moving point, line segment, changing angle, and the area of the figure as the basic conditions, give one or more variables, and require the determination of other relationships such as functions between the variable and other quantities, or when the variable is a fixed value under certain conditions, the relevant calculation and comprehensive solution are carried out, and the solution to this kind of problem is generally based on the motion of the point and the change process of the figure.

The techniques for solving the first moving point problem are as follows:

Method 1: 1. Find the datum coordinates of the moving point, that is, the starting coordinates of the movement.

2. Calculate the coordinates after the movement of the moving point:

Movement to the right: coordinates after movement = datum coordinates + movement distance.

Left movement: coordinates after movement = datum coordinates - distance traveled.

3. Indicate the length of the line segment: the right end of the line segment indicates the number of file resistance - the number represented by the left end of the line segment.

4. Column equations: according to the relationship of motion or the conditions in the problem, list the equations, and the unknowns are usually the motion time t, velocity v or the coordinates sought; Solving.

Method 2: 1. The known relevant quantities are all marked on the graph, and the known quantities that can be found nearby are also marked on the graph, and the conclusions that can be obtained are all marked next to the graph, so as to facilitate the application and use of the corresponding conclusions in the next step.

In this process, you can also use some tools such as geometric drawing board or drawing brain to supplement the movement process of the point after the key point is marked on the map, and take some tools to do exercise assistance to help find the key movement rules.

2. According to the known correlation given by the moving point, find the motion law of the moving point and the relationship between the distance of the movement, the length and distance of the movement and the time. Find the movement point with the regularity of the movement and the trajectory of the process of movement, and the quantity related to this.

3. According to the time or distance in the movement, or the amount that has been used in the whole process, the commonly used ones are time and distance, and some unknown constants are mentioned at the beginning.

4. Complete the conversion. Transform the moving point into the distance of motion, transform the distance of motion into related expressions, convert expressions into algebraic formulas, and then use algebraic equations to solve the problem of key regularity.

Here are some tips for solving the moving point problem: <>

1. Establish a coordinate system: represent the geometry involved in the problem in the plane Cartesian coordinate system.

2. Find the coordinates of special points: for example, the intersection point, starting point, and end point of the motion trajectory.

3. Find the equation of the trajectory: the trajectory can be a straight line, a parabola, a circle, an ellipse, etc., which needs to be solved according to the problem.

4. Use conditions to solve problems: Usually some restrictions will be given in the problem, such as the distance between two points, speed, time, etc.

5. With the help of auxiliary lines: When solving problems, you can use auxiliary lines to help solve problems, such as establishing perpendicular lines, parallel lines, etc.

6. Vectors can be used in spatial moving point problems: Vector knowledge is required for spatial moving point problems. <>

In the first year of junior high school, the moving point problem is a classic geometric problem. The moving point problem refers to the movement of a point along a specific path in the coordinate system of the right-angle mold and coordinate system of the flat code, and the coordinates or specific properties of the point at a certain time are found.

In conclusion, solving the moving point problem requires a combination of knowledge of geometry, algebra, and physics, as well as the use of appropriate methods at the right time, and the cultivation of flexible thinking.

The math skills for the third year of the moving point questions are as follows:

1. Use the principle of relative motion to solve the problem of the moving point of the middle school entrance examination.

In the process of learning physics knowledge in middle school, the principle of relative motion is generally adopted to solve those kinematic problems with greater complexity, and the rationality of the selection of reference objects will have a direct impact on the overall solution quality and efficiency. If the selected reference material is very much in line with the actual problem analysis needs, then the problem can be greatly simplified.

In the same way, if the principle of relative motion can be flexibly used in the process of solving the type of problem of the moving point in the process of solving the problem, and the relationship between the fixed point and the moving point can be effectively handled, then it will often play a very critical role in simplifying the problem and improve the efficiency of problem solving.

2. Grasp the repentance and enlightenment system of movement and stillness, and solve the problem of moving points in the middle school entrance examination.

If it is difficult to determine the actual trajectory of the moving point when solving the moving point problem, then the relationship between the dynamic and the static can be fully utilized, and the strategy of "dynamic and fixed conversion" can be adopted, and the moving point problem can be directly determined as the trajectory after conversion, so that the strategy of "dynamic conversion" can be used to simplify the moving point problem, reduce the difficulty of its solution, and finally transform some non-obvious moving point problems into a more familiar mathematical solution model with simple rules.

3. Summarize the solutions of common question types and solve the problems of the moving points of the middle school entrance examination.

By inducting, summarizing and analyzing the question types about moving points in the mathematics test paper of the high school entrance examination, it can be seen that it mainly includes two types: "moving point" and "moving line", of which the former can also be divided into single moving points or double moving points according to the number of moving points.

At the same time, in the specific moving point problems involved, there are often function problems, shortest distance problems, existential problems, most value problems, etc., so in order to solve the corresponding mathematical problems more quickly, you can combine these common moving point problem types to do a good job of induction and summary of the problem solving methods, so as to continuously improve the ability to solve the moving point problem.