Computational power in Mathematics
Publish: 2021-04-22 00:47:42
1. Generally, you can't be hungry or rich, but the iron rice bowl is still very good
2. I hope the following answers can help you:
1. Strengthen the teaching of basic knowledge and basic skills, and improve the accuracy of calculation.
the basic knowledge in mathematics is the basis of calculation, which has guiding significance for calculation. The basic knowledge is confused, fuzzy, and the basic knowledge is not solid. In the past, it is the root cause of calculation errors, Therefore, to strengthen and implement the double base teaching is a very practical problem to improve the operation ability, which requires students to do:
(1) memorize some important data formulas and rules, because accuracy is the basic requirement of operation, and correct memory formulas and rules are the premise of accurate operation. Among the mathematical concepts, formulas, rules and properties, some are the basis of operation, explaining the reasons for "why it can be done like this", and some are the methods and steps of operation. It gives the proceres of how to do, that is, algorithms. Students learn the relevant concepts, properties and formulas, and memorize, rules and steps on the basis of understanding, Then, through a series of operation activities (i.e. practice), some kind of operation skills are graally formed
(2) correctly understand the concepts and definitions, and master the derivation of formulas. Only by understanding the derivation of some concepts and formulas, can we achieve the positive, reverse and flexible use of formulas, so as to improve the computing ability. The reason of incorrect operation in mathematics learning is often the result of fuzzy concept, formula, rule forgetting, confusion or rigid application
2. Strengthen the reasoning training of scientific system to improve the rapidity of operation
the poor operation ability is often caused by the weak thinking ability. In teaching, we should strengthen the reasoning training on the basis of students' mastering the basic knowledge. In normal practice, we should make sure that there is a basis step by step, there are sufficient reasons, and pay attention to the sequence of operation. Generally, we should pay attention to the following aspects:
1) training must be orderly. Practice must be planned and carried out step by step. In mathematics teaching, practice can be divided into three stages: first, imitation practice stage. This is an exercise carried out under the example demonstration of the teacher after learning the new knowledge. The difficulty of the selected exercises is not high and the change is not big. Students are required to operate according to the steps and rules of the examples to ensure the correctness of the operation. At this time, it is not appropriate to put forward the speed requirements; Second, the mastery stage. This is a study organized on the basis of students' preliminary mastery of knowledge and skills. The difficulty of the exercises is appropriately increased, and the forms of the exercises are changed. Students are not only required to operate correctly, but also required to summarize and summarize the process, basis and methods of operation after obtaining the correct answers, so as to promote the operation mode to the theoretical level; Third, comprehensive application stage. At this time, we can choose some difficult comprehensive questions to train students' ability to determine the direction of operation and flexibly use the rules
(2) carry out variant exercises. In order to make students skillful, we must organize variant exercises. The so-called variant practice is the change of concepts and rules under the condition that other effective learning conditions remain unchanged. For mathematical operations, it is to change the non essential characteristics of the problem and keep its structural components unchanged. The concrete ways include the change of expression of mathematical sentences, the exchange of conditions and conclusions, the change of problems and backgrounds, etc
(3) understand the effect of practice in time and correct the mistakes in practice in time. In ability practice, it is an effective way to let students know the effect of practice in time. Psychological research shows that if the following feedback information is provided to the students who are carrying out the ability training: ① know the score of each exercise; ② encourage and urge them continuously in the process of practice; ③ analyze the mistakes in practice, then the practice effect will be significantly improved. This is because, on the one hand, students know the problem according to the feedback information, so as to adjust the learning activities and make the practice more effective; On the other hand, it also increases learning motivation to strive for better results or avoid making similar mistakes again
3. The training of thinking flexibility in the process of operation
because mathematical operation is an intelligent operation with clear direction and in line with certain rules, after a certain amount of practice, this kind of operation experience will form a fixed reaction mode and play a tendentious role in the selection of operation direction in subsequent learning, This is the "set" phenomenon in learning. When the formed inertial thinking is consistent with the way to solve new problems, it can quickly respond and get the correct answer. The phenomenon of "shrinking" and "skipping" appears in the process of calculation. This is the positive role of the fixed trend, and also the sign of students mastering knowledge and skills. For example, through the study of "quadratic equation of one variable", students have mastered the skills of using formula method and factorization method to solve quadratic equation of one variable. In the later study of quadratic function, when they encounter the operations related to quadratic equation of one variable, they will quickly make the correct response. When the conventional way of thinking is not completely consistent with or contrary to the solution of new problems, it can not be solved in a simple and flexible way, and the operation process is tedious and tedious, which leads to the wrong solution of the problem. This is the negative effect of stereotype. In practical teaching, we should overcome and prevent the negative effect of "stereotype" and cultivate the flexibility of students' calculation
4. Pay attention to cultivate students' ability of operation rationality
reasonable calculation is to make full use of operation law, proct invariance and quotient invariance, change the data and order of operation, and make the operation as simple, fast and correct as possible. The cultivation of students' simple operation ability is not only the improvement of operation ability, because in the process of cultivation, it must involve the cultivation of observation ability, inctive ability and other abilities, so the cultivation of simple operation ability is actually the cultivation of comprehensive ability. At the same time, it is necessary to cultivate students' overall view of mathematical operation. Before calculation, students should have an overall view of the overall situation. They should grasp the steps of operation, what should be calculated first and then, what are the characteristics of the numbers in the title, and what contains information, etc.
1. Strengthen the teaching of basic knowledge and basic skills, and improve the accuracy of calculation.
the basic knowledge in mathematics is the basis of calculation, which has guiding significance for calculation. The basic knowledge is confused, fuzzy, and the basic knowledge is not solid. In the past, it is the root cause of calculation errors, Therefore, to strengthen and implement the double base teaching is a very practical problem to improve the operation ability, which requires students to do:
(1) memorize some important data formulas and rules, because accuracy is the basic requirement of operation, and correct memory formulas and rules are the premise of accurate operation. Among the mathematical concepts, formulas, rules and properties, some are the basis of operation, explaining the reasons for "why it can be done like this", and some are the methods and steps of operation. It gives the proceres of how to do, that is, algorithms. Students learn the relevant concepts, properties and formulas, and memorize, rules and steps on the basis of understanding, Then, through a series of operation activities (i.e. practice), some kind of operation skills are graally formed
(2) correctly understand the concepts and definitions, and master the derivation of formulas. Only by understanding the derivation of some concepts and formulas, can we achieve the positive, reverse and flexible use of formulas, so as to improve the computing ability. The reason of incorrect operation in mathematics learning is often the result of fuzzy concept, formula, rule forgetting, confusion or rigid application
2. Strengthen the reasoning training of scientific system to improve the rapidity of operation
the poor operation ability is often caused by the weak thinking ability. In teaching, we should strengthen the reasoning training on the basis of students' mastering the basic knowledge. In normal practice, we should make sure that there is a basis step by step, there are sufficient reasons, and pay attention to the sequence of operation. Generally, we should pay attention to the following aspects:
1) training must be orderly. Practice must be planned and carried out step by step. In mathematics teaching, practice can be divided into three stages: first, imitation practice stage. This is an exercise carried out under the example demonstration of the teacher after learning the new knowledge. The difficulty of the selected exercises is not high and the change is not big. Students are required to operate according to the steps and rules of the examples to ensure the correctness of the operation. At this time, it is not appropriate to put forward the speed requirements; Second, the mastery stage. This is a study organized on the basis of students' preliminary mastery of knowledge and skills. The difficulty of the exercises is appropriately increased, and the forms of the exercises are changed. Students are not only required to operate correctly, but also required to summarize and summarize the process, basis and methods of operation after obtaining the correct answers, so as to promote the operation mode to the theoretical level; Third, comprehensive application stage. At this time, we can choose some difficult comprehensive questions to train students' ability to determine the direction of operation and flexibly use the rules
(2) carry out variant exercises. In order to make students skillful, we must organize variant exercises. The so-called variant practice is the change of concepts and rules under the condition that other effective learning conditions remain unchanged. For mathematical operations, it is to change the non essential characteristics of the problem and keep its structural components unchanged. The concrete ways include the change of expression of mathematical sentences, the exchange of conditions and conclusions, the change of problems and backgrounds, etc
(3) understand the effect of practice in time and correct the mistakes in practice in time. In ability practice, it is an effective way to let students know the effect of practice in time. Psychological research shows that if the following feedback information is provided to the students who are carrying out the ability training: ① know the score of each exercise; ② encourage and urge them continuously in the process of practice; ③ analyze the mistakes in practice, then the practice effect will be significantly improved. This is because, on the one hand, students know the problem according to the feedback information, so as to adjust the learning activities and make the practice more effective; On the other hand, it also increases learning motivation to strive for better results or avoid making similar mistakes again
3. The training of thinking flexibility in the process of operation
because mathematical operation is an intelligent operation with clear direction and in line with certain rules, after a certain amount of practice, this kind of operation experience will form a fixed reaction mode and play a tendentious role in the selection of operation direction in subsequent learning, This is the "set" phenomenon in learning. When the formed inertial thinking is consistent with the way to solve new problems, it can quickly respond and get the correct answer. The phenomenon of "shrinking" and "skipping" appears in the process of calculation. This is the positive role of the fixed trend, and also the sign of students mastering knowledge and skills. For example, through the study of "quadratic equation of one variable", students have mastered the skills of using formula method and factorization method to solve quadratic equation of one variable. In the later study of quadratic function, when they encounter the operations related to quadratic equation of one variable, they will quickly make the correct response. When the conventional way of thinking is not completely consistent with or contrary to the solution of new problems, it can not be solved in a simple and flexible way, and the operation process is tedious and tedious, which leads to the wrong solution of the problem. This is the negative effect of stereotype. In practical teaching, we should overcome and prevent the negative effect of "stereotype" and cultivate the flexibility of students' calculation
4. Pay attention to cultivate students' ability of operation rationality
reasonable calculation is to make full use of operation law, proct invariance and quotient invariance, change the data and order of operation, and make the operation as simple, fast and correct as possible. The cultivation of students' simple operation ability is not only the improvement of operation ability, because in the process of cultivation, it must involve the cultivation of observation ability, inctive ability and other abilities, so the cultivation of simple operation ability is actually the cultivation of comprehensive ability. At the same time, it is necessary to cultivate students' overall view of mathematical operation. Before calculation, students should have an overall view of the overall situation. They should grasp the steps of operation, what should be calculated first and then, what are the characteristics of the numbers in the title, and what contains information, etc.
3. How to improve high school mathematics calculation ability
if you want to improve the high school mathematics calculation ability, you should use your brain more, find the calculation rules, pay more attention and do more, and then you can slowly improve your calculation ability.
if you want to improve the high school mathematics calculation ability, you should use your brain more, find the calculation rules, pay more attention and do more, and then you can slowly improve your calculation ability.
4. A person's mathematical calculation ability mainly includes three aspects:
1. Accuracy of calculation results
2
3< In order to improve the mathematical calculation ability of primary school students, efforts should be made in the following four aspects:
first, let students master the operation rules: in primary school, students should learn three kinds of numbers - integers (natural numbers), decimals and fractions, Each kind of operation of each kind of number has its own specific operation rules, and is proficient in all kinds of operations< Second, pay attention to the cultivation of students' estimation ability: the new curriculum includes the cultivation of students' estimation ability, which fully reflects the importance of estimation in mathematical calculation and real life. Estimation ability is also a very important aspect of a person's calculation ability. Good estimation ability has been proved to have four advantages in practice:
1. Help us predict the calculation results; 2
2. It can improve the ability of mathematical analysis
3. It can solve real life problems
4. Check whether the results are basically correct.
1. Accuracy of calculation results
2
3< In order to improve the mathematical calculation ability of primary school students, efforts should be made in the following four aspects:
first, let students master the operation rules: in primary school, students should learn three kinds of numbers - integers (natural numbers), decimals and fractions, Each kind of operation of each kind of number has its own specific operation rules, and is proficient in all kinds of operations< Second, pay attention to the cultivation of students' estimation ability: the new curriculum includes the cultivation of students' estimation ability, which fully reflects the importance of estimation in mathematical calculation and real life. Estimation ability is also a very important aspect of a person's calculation ability. Good estimation ability has been proved to have four advantages in practice:
1. Help us predict the calculation results; 2
2. It can improve the ability of mathematical analysis
3. It can solve real life problems
4. Check whether the results are basically correct.
5. How to improve students' computational ability in Mathematics Teaching
computational ability is a basic mathematical ability. It is an important task of primary school mathematics teaching to cultivate primary school students' computational ability. In recent years, it is not difficult to find that the phenomenon of students losing points e to calculation errors is more and more serious. The calculation ability of primary school students has a downward trend compared with the past. As a math teacher, we should consciously cultivate students' computing ability in the usual teaching< First, we should pay attention to the basic knowledge of mathematics. In order to get the calculation results, we should first consider what mathematical concepts, operation laws, operation properties, operation rules and calculation formulas to use. Therefore, it is the premise for students to fully understand and master these basic knowledge. Some students make mistakes in the calculation in the exam, not because they can't really calculate, but because the operation law or the operation law is not clear, resulting in calculation errors. Only when the relevant basic knowledge is explained clearly and the students really master it, the students will not make mistakes in calculation
if students are calculating 125 × At 28:00, many students do this: 125 × 28=125 × 20+8=125 × 20 + 125 = 2500 + 125 = 2625. But in the calculation, e to the wrong use of the multiplication allocation law, the final calculation result is wrong. Just imagine, when our teacher teaches the law of distribution by multiplication, if he can let the students really understand the essence of the law and know that the law is to multiply the sum of two numbers by the third number into the sum of these two numbers multiplied by the third number, the students will not make the above mistakes in calculation
especially when the students reach the senior grade, their basic knowledge of mathematics has been very rich. Therefore, they should not be in a hurry to achieve success in teaching, but should help the students learn to sort out the basic knowledge they have learned and use it flexibly when doing problems< Second, strengthen the training of basic skills
as the saying goes, "the fist never leaves the hand, the tune never leaves the mouth", it is also the truth to improve students' computing ability. In the usual teaching, teachers should strengthen the training of students' computing ability and correct some errors in the calculation in time. Only when we practice more at ordinary times can we improve the accuracy of students' calculation. Otherwise, students will make mistakes in calculation. For example: in the calculation of 3.5 × At 20:00, some students answered 3.5 × 2, get 7, forget the "0" at the end of "20". The other answer is 35 × 20 = 700, no attention to the decimal point in 3.5. All these are caused by insufficient practice. In the calculation practice, strengthening the basic skills training is an important link to improve the calculation ability. For example, when calculating the four operations of decimal and fraction, we often encounter that the students' algorithm is correct but the result is wrong. The reasons include the errors of approximate score and general score, the errors of mutual conversion, and the problems of oral calculation within 100. All these reflect the defects of students' basic skills. Therefore, in the practice, we should pay more attention. Strengthen the training of basic skills
in addition, helping students summarize some regular things can greatly improve their computing skills. For example: the mixed operation of fraction and decimal addition and subtraction, generally speaking, it is relatively simple to calculate with decimal, but judging whether all fractions can be converted into finite decimal has become the key point of this kind of calculation. With the breakthrough of this key point, students' operation speed will be accelerated, and their calculation skills will also be improved
thirdly, cultivate good calculation habits, which is a reliable guarantee for students to calculate correctly. In teaching, we can often find that many students make mistakes in calculation, not because they do not understand the calculation theory correctly, nor do they master the calculation method, but because they do not have a good calculation habit. Therefore, it is particularly important to cultivate students to develop a good calculation habit. I think we should develop the following habits:
see clearly. Because students look at the topic too fast, sometimes they will read the number wrong, such as 234 as 243, sometimes they will read the operation symbols wrong, upside down and so on. Therefore, we should let students form the habit of reading the number in the topic clearly, not too fast, but memorize the whole, not reading one by one, and can quickly compare with the original number after writing, and so on, So as to rece the calculation error caused by misreading
write neatly. Nonstandard writing is also a common reason for calculation errors. When students are calculating, they sometimes look at it by mistake because of the illegible handwriting, such as 6 and 0, 1 and 7, 3 and 8; Some write, write, erase, and blur; Some vertical writing is not standard, the number is not aligned and so on, may cause the calculation error. Therefore, in teaching, it is necessary to require students to write neat, standard format, to urge students to write numbers correctly and clearly. Pay attention to this point, and the errors in the calculation will be reced a lot
careful calculation. Sometimes mistakes in calculation are also caused by students' careless calculation × 3 becomes 5, or carry forgets to add, or abdicate forgets to subtract, and so on. Therefore, in teaching, do not blindly require students to calculate fast, but first to calculate correctly, and then put forward the corresponding speed requirements on the basis of the correct, which can also improve the accuracy of students' calculation
check carefully. Checking and checking calculation is not only an effective measure to ensure correct calculation, but also a means to promote students' understanding of calculation process and calculation skills. Students can further understand the inverse operation relationship between addition and subtraction, multiplication and division through checking calculation. However, e to weak willpower, pupils can not consciously adhere to the inspection and checking, perfunctorily look around, and do not carry out the inspection and checking in the real sense. Therefore, in teaching, we should pay attention to teaching students the methods of checking and checking calculation (such as inverse calculation, estimation, recalculation, etc.), and supervise them to form the habit of checking. In addition, we can also let students who have checked out mistakes and got good results give their own experience at the right time, so that students can fully feel the success brought by careful checking and checking calculation, Consciously develop the habit of active checking
in short, the improvement of students' computing ability is not an overnight thing. In normal teaching, teachers should start from the characteristics of teaching materials, from the reality of students, from the psychological characteristics of children, contact real life, contact game activities, and integrate multimedia, so as to create a teaching environment full of children's interest The dynamic learning environment makes the boring computing teaching radiate new vitality.
computational ability is a basic mathematical ability. It is an important task of primary school mathematics teaching to cultivate primary school students' computational ability. In recent years, it is not difficult to find that the phenomenon of students losing points e to calculation errors is more and more serious. The calculation ability of primary school students has a downward trend compared with the past. As a math teacher, we should consciously cultivate students' computing ability in the usual teaching< First, we should pay attention to the basic knowledge of mathematics. In order to get the calculation results, we should first consider what mathematical concepts, operation laws, operation properties, operation rules and calculation formulas to use. Therefore, it is the premise for students to fully understand and master these basic knowledge. Some students make mistakes in the calculation in the exam, not because they can't really calculate, but because the operation law or the operation law is not clear, resulting in calculation errors. Only when the relevant basic knowledge is explained clearly and the students really master it, the students will not make mistakes in calculation
if students are calculating 125 × At 28:00, many students do this: 125 × 28=125 × 20+8=125 × 20 + 125 = 2500 + 125 = 2625. But in the calculation, e to the wrong use of the multiplication allocation law, the final calculation result is wrong. Just imagine, when our teacher teaches the law of distribution by multiplication, if he can let the students really understand the essence of the law and know that the law is to multiply the sum of two numbers by the third number into the sum of these two numbers multiplied by the third number, the students will not make the above mistakes in calculation
especially when the students reach the senior grade, their basic knowledge of mathematics has been very rich. Therefore, they should not be in a hurry to achieve success in teaching, but should help the students learn to sort out the basic knowledge they have learned and use it flexibly when doing problems< Second, strengthen the training of basic skills
as the saying goes, "the fist never leaves the hand, the tune never leaves the mouth", it is also the truth to improve students' computing ability. In the usual teaching, teachers should strengthen the training of students' computing ability and correct some errors in the calculation in time. Only when we practice more at ordinary times can we improve the accuracy of students' calculation. Otherwise, students will make mistakes in calculation. For example: in the calculation of 3.5 × At 20:00, some students answered 3.5 × 2, get 7, forget the "0" at the end of "20". The other answer is 35 × 20 = 700, no attention to the decimal point in 3.5. All these are caused by insufficient practice. In the calculation practice, strengthening the basic skills training is an important link to improve the calculation ability. For example, when calculating the four operations of decimal and fraction, we often encounter that the students' algorithm is correct but the result is wrong. The reasons include the errors of approximate score and general score, the errors of mutual conversion, and the problems of oral calculation within 100. All these reflect the defects of students' basic skills. Therefore, in the practice, we should pay more attention. Strengthen the training of basic skills
in addition, helping students summarize some regular things can greatly improve their computing skills. For example: the mixed operation of fraction and decimal addition and subtraction, generally speaking, it is relatively simple to calculate with decimal, but judging whether all fractions can be converted into finite decimal has become the key point of this kind of calculation. With the breakthrough of this key point, students' operation speed will be accelerated, and their calculation skills will also be improved
thirdly, cultivate good calculation habits, which is a reliable guarantee for students to calculate correctly. In teaching, we can often find that many students make mistakes in calculation, not because they do not understand the calculation theory correctly, nor do they master the calculation method, but because they do not have a good calculation habit. Therefore, it is particularly important to cultivate students to develop a good calculation habit. I think we should develop the following habits:
see clearly. Because students look at the topic too fast, sometimes they will read the number wrong, such as 234 as 243, sometimes they will read the operation symbols wrong, upside down and so on. Therefore, we should let students form the habit of reading the number in the topic clearly, not too fast, but memorize the whole, not reading one by one, and can quickly compare with the original number after writing, and so on, So as to rece the calculation error caused by misreading
write neatly. Nonstandard writing is also a common reason for calculation errors. When students are calculating, they sometimes look at it by mistake because of the illegible handwriting, such as 6 and 0, 1 and 7, 3 and 8; Some write, write, erase, and blur; Some vertical writing is not standard, the number is not aligned and so on, may cause the calculation error. Therefore, in teaching, it is necessary to require students to write neat, standard format, to urge students to write numbers correctly and clearly. Pay attention to this point, and the errors in the calculation will be reced a lot
careful calculation. Sometimes mistakes in calculation are also caused by students' careless calculation × 3 becomes 5, or carry forgets to add, or abdicate forgets to subtract, and so on. Therefore, in teaching, do not blindly require students to calculate fast, but first to calculate correctly, and then put forward the corresponding speed requirements on the basis of the correct, which can also improve the accuracy of students' calculation
check carefully. Checking and checking calculation is not only an effective measure to ensure correct calculation, but also a means to promote students' understanding of calculation process and calculation skills. Students can further understand the inverse operation relationship between addition and subtraction, multiplication and division through checking calculation. However, e to weak willpower, pupils can not consciously adhere to the inspection and checking, perfunctorily look around, and do not carry out the inspection and checking in the real sense. Therefore, in teaching, we should pay attention to teaching students the methods of checking and checking calculation (such as inverse calculation, estimation, recalculation, etc.), and supervise them to form the habit of checking. In addition, we can also let students who have checked out mistakes and got good results give their own experience at the right time, so that students can fully feel the success brought by careful checking and checking calculation, Consciously develop the habit of active checking
in short, the improvement of students' computing ability is not an overnight thing. In normal teaching, teachers should start from the characteristics of teaching materials, from the reality of students, from the psychological characteristics of children, contact real life, contact game activities, and integrate multimedia, so as to create a teaching environment full of children's interest The dynamic learning environment makes the boring computing teaching radiate new vitality.
6. Do it step by step, there's no secret.
generally speaking, the problem maker certainly doesn't want to embarrass you, so the result of simplification is usually very simple (many problems are pushed back by the problem maker). If you calculate the result is abnormal, 670% of it is your wrong calculation.
in fact, I'm dizzy (I'm a sophomore in senior high school) and it's wrong every time, but it's not that I didn't play my ability, It's just that your ability is not good. If you have a good ability, it doesn't take much brain to come up with ideas. When you simplify, your mind is very clear, and you are not afraid of large amount of calculation. I believe that you should eliminate all of them in less than five minutes. If you have poor ability and finally come up with ideas, you will not be able to read the letters, and you will always bring in the wrong ones, In fact, it's a way to improve the analytic geometry ability, although it seems that it doesn't touch the edge
as for the calculation ability
our junior high school teachers have given us random numbers to do for a period of time, which is generally not right, such as 134 / 3456 + 345 / 875 =? 3467x ^ 2 + 486x-34567 = 34576... If you don't have to do it yourself, you can improve your calculation ability invisibly
and if you can do it with your mind, you can do it with your mind. For example, 19 * 17 = 323 can also improve your mathematical ability (I created it, very effective)
generally speaking, the problem maker certainly doesn't want to embarrass you, so the result of simplification is usually very simple (many problems are pushed back by the problem maker). If you calculate the result is abnormal, 670% of it is your wrong calculation.
in fact, I'm dizzy (I'm a sophomore in senior high school) and it's wrong every time, but it's not that I didn't play my ability, It's just that your ability is not good. If you have a good ability, it doesn't take much brain to come up with ideas. When you simplify, your mind is very clear, and you are not afraid of large amount of calculation. I believe that you should eliminate all of them in less than five minutes. If you have poor ability and finally come up with ideas, you will not be able to read the letters, and you will always bring in the wrong ones, In fact, it's a way to improve the analytic geometry ability, although it seems that it doesn't touch the edge
as for the calculation ability
our junior high school teachers have given us random numbers to do for a period of time, which is generally not right, such as 134 / 3456 + 345 / 875 =? 3467x ^ 2 + 486x-34567 = 34576... If you don't have to do it yourself, you can improve your calculation ability invisibly
and if you can do it with your mind, you can do it with your mind. For example, 19 * 17 = 323 can also improve your mathematical ability (I created it, very effective)
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