Reflection on vertical bisector teaching

Part 1: Reflection on the teaching of vertical bisector

The nature theorem and the decision theorem of the vertical bisector of the line segment can optimize the method of proofing the subject. This is the most prominent place in this lesson. The deeper feeling is that the students get the joy of new knowledge and new methods. It is beneficial to the students' "study case". The teaching process we arranged in this lesson is: drawing the vertical bisector of the line, studying and proving the nature of the vertical bisector of the line segment; understanding the nature of the vertical bisector of the line segment, learning examples 1, 2, 3; asking questions: by PA =PB, can explain 1. Is the point P on the vertical bisector of the AB segment on the line? 2. Is the straight line passing through point P the vertical bisector of line segment AB? The study of the decision to transition to the vertical bisector of the line segment; when proving the conjecture, it is proposed whether the P is the vertical bisector of the line segment AB, and the student's response is quite enthusiastic. Some students have proposed PC⊥AB and C for the foot. Try to prove AC=BC; some students proposed to take the midpoint C of AB, connect the PC, prove PC⊥AB, the student discussed the proof, got the judgment theorem of the vertical bisector of the line segment, and summed up the proof when it was “Vertical "Separate" or "divide equally, prove vertical", thus realize that "a little bit is impossible to make a straight line to ensure that both vertical and even points", the second question of thinking is easy to explain, if there are two such points P According to the "two points to determine a straight line", the vertical bisector of the known line segment can be made, and the research of the example 4 is brought out in a timely manner; finally, the promotion learning is carried out, and the new knowledge content can be harvested in the training.

Part 2: Reflection on the teaching of vertical bisector

In response to the problems in this class, I made the following reflections: First of all, when preparing lessons, we must grasp the difficulties, arrange the content of a class, and grasp the time of a class; secondly, it must be reflected in the students. The principle of being the main one is to combine practice and practice, giving students enough time to practice and fully understand the acceptance of new knowledge. In the future teaching, I will not constantly improve my own shortcomings.

Part 3: Reflection on the teaching of vertical bisector

1. Because the preparation before class is relatively complete, the whole teaching process is clearer, the steps are smoother, the teaching is more natural, and the language is more concise.
2. The enthusiasm of student participation is not high enough, the participation is not wide enough, the teaching effect may not be satisfactory, and the individual differences in knowledge absorption will be relatively large.
3. Due to the relatively large capacity of this lesson, the teaching speed will be accelerated, which will inevitably cause good students to absorb faster and more, and the later students will not be able to absorb it.
4. When students are asked to summarize the new theorem and the inverse theorem, because of the time rush, only a small number of students will be described in a fluent way, and the rest of the students will not be able to pass, so it is difficult to practice.
Improvement opinion
The introduction of the new lesson can be slowed down and explained in more detail. When the students can't answer the questions raised by the teacher for a while, I can't rush to make the correct answer public, but should be properly guided. This lesson The capacity can be reduced, which can explain the content more thoroughly and enable more students to master the new knowledge.

Part 4: Reflection on the teaching of vertical bisector

The vertical bisector of the line segment plays an important role in geometric mapping, proof, and calculation. The property theorem of the vertical bisector of the line segment is an important way to prove that the line segment is equal. Its inverse theorem is often used to prove that a straight line is a line segment. The vertical line or point is the midpoint of a line segment.
In the design of the lesson plan, I combined the content of the textbook, and explored how to introduce the new lesson, lead to the theorem and proof. In the process of introducing the new lesson, I first let the student make a vertical bisector MN of the line AB, which is taken on the MN. A little bit P, let students measure the length of PA, PB, and guide students to observe and discuss the relationship between the two lengths of each person: What conclusions are obtained? The student replies: PA=PB. Then let the students take a try, the two lengths are also equal, thus guiding the students to guess the nature theorem of the vertical bisector of the line segment. In this process, the students actively participate in this process. In the process of teaching, students can draw conclusions by drawing, observing, and measuring the quantity. Thus, the process of knowledge formation is transformed into the process of students' self-participation, discovery and exploration. In teaching, students are guided to analyze the themes of nature theorem. And draw conclusions, draw the known and verified, through the analysis of the method of proof of the nature theorem by the students, this process is not only the process of exploration but also the process of mobilizing students to think about the brain. Only when students think about it, can they truly understand the vertical bisector of the line segment. The property theorem, and the proof method. On this basis, if there are two points to the ends of the line segment at the same distance, what kind of line should such a point be? From the condition, the vertical bisector of the point line is derived, and the inverse theorem of the property theorem is derived. The above two theorems make the student further know that the vertical bisector of the line segment can be regarded as all points to the distance between the two ends of the line segment. The collection can help students understand the theory that comes from practice and serve the practice. It can also improve their enthusiasm for learning and deepen their understanding of the knowledge they have learned. Guide students to use the vertical bisector of the line segment they are learning. The nature theorem and the inverse theorem to prove that avoiding the use of triangles and so on. In order to enable students to master the flexible use of the two theorems, students can complete two examples to achieve the purpose of consolidating knowledge. Finally, the summary point O is triangle three. The intersection of the vertical bisector, the distance from this point to the three vertices is equal.

Part V: Reflection on the teaching of vertical bisector

The purpose of this lesson is to understand and grasp the theorem of the vertical bisector of the line segment and its inverse theorem, and to use the theorem to prove or calculate; know that the vertical bisector of the line segment is a set of points equal to the distance between the two ends of the line segment; The process of operation, conjecture, proof, application, the idea of ​​infiltrating the set and the way of thinking to determine the position of a certain point by the method of orbit; by participating in classroom activities, knowing that mathematics problems originate from life practice, and in turn, mathematics serves life practice. To increase interest in learning mathematics.
First, set the scene to introduce a new lesson. In order to facilitate the residents' life, the Putuo District Government plans to build a shopping center between the three residential quarters A, B and C. I would like to ask where the shopping mall should be built to make it The distance between the three cells is equal?
Then through practical exploration and conjecture, the proposition "any point on the vertical bisector of the line segment is equal to the distance between the two endpoints of the line segment." Prove the correctness of this proposition. Obtain the property theorem of the vertical bisector of the line segment. Students then speak their inverse theorems to develop students' ability to reverse thinking and mathematical language expression. This lesson is more concerned with life practice. Mathematical problems are revealed to expose students' interest in learning mathematics. Make students feel that mathematics problems stem from life practice, which in turn serves life practice.