2. Write a math diary with the word 100 as follows: Today's math class talked about XXXX (such as Elementary Arithmetic).
Then write down the content of the study (definition and proof of theorem, important examples the teacher talked about, and any new solutions). Then you can write about the difficulties you encountered in doing your homework. If you find it easy, you can also write down good reasons for learning this part, such as listening carefully in class or previewing in advance.
Let's talk about the mistakes made by ourselves or our classmates and the ways to correct them. You can also write like this: I came home from school today and suddenly saw a lot of people in front of a shop.
When I took a closer look, it turned out that the store was engaged in promotional activities. You can answer a question by paying one yuan. If you can answer correctly within 30 seconds, you will win the 30 yuan. I saw others losing one after another, and I thought, What's so hard about it? I paid one yuan out of curiosity.
I followed my boss into the store, and he began to ask, "Xiaoming went to the bookstore to buy books, and bought 17 books with 99 yuan money. How much did he spend? " As soon as he finished, he showed a sly look and began to time. As time went on, my sweat dripped down. How to calculate this 99 times 17 without vertical calculation? At this moment, it dawned on me. There is a page in "Daily Practice of Oral Calculations" that says otherwise: The quick calculation method of multiplying a number within 100 by 99 is to multiply this number by 100 first, and then subtract this number.
Thinking of this, I blurted out: "1683." As soon as I finished, the boss almost fell to the ground. He looked at the timer for only 28 seconds and gave me the money helplessly.
I walked out of the store with 30 yuan and looked at the envious eyes of others, not to mention how happy I was. At this time, I thought: Mathematics is not only the calculation of 1+ 1, but also has a wide range of uses in life. Besides, math is used for shopping and other things.
So, I want to say it again: "Mathematics is really useful.
Today, my mother took me to the stationery store to buy stationery.
When I came to the stationery store, my mother asked me to choose my own stationery. I cheerfully ran to the counter and politely said to the salesman, "Hello, Aunt, I want to buy a schoolbag, a composition book, a pencil case, a pencil and an eraser." "Ok, just a moment, please."
"Well, how much is a * *?" I asked. Aunt said, "A schoolbag 35 yuan, a composition book 15 yuan, a pencil box 8 yuan, a pencil 1 yuan and an eraser 2 yuan. How much is a child? " 35+ 15+8+ 1+2 I calculated and answered, "A ***6 1 yuan."
Looking back at my mother, my mother gave 10 1 yuan to get 40 yuan money back. I asked my mother inexplicably, "Why should I give 1 yuan more?" My mother said to me, "That way, she can give me the whole change."
Oh, I see. Isn't this the ten-point method in applied mathematics? It seems that there is mathematics everywhere in life.
4. How to write a model essay for the second-grade pupils in math diary: (For reference) This Sunday in January, at noon, I was doing my math summer homework in math diary.
I wrote and wrote, but unfortunately I met a very difficult problem. I've thought about it for a long time, and I can't figure out why. The problem is this: there is a cuboid, the product of the front and the upper two areas is 209 square centimeters, and its length, width and height are prime numbers. Find its volume.
I saw it and thought: this question is really difficult! Only knowing the product of two surface areas, the volume must also know the length, width and height, but there is no hint at all. How does this start? Just as I was scratching my head, a colleague of my mother came.
He taught me to use the idea of equation to solve it first, but I am not very familiar with this method of equation. So, he taught me another way: list the numbers first, and then exclude them one by one.
First, we listed a lot of numbers according to the requirements of the topic, such as: 3, 5, 7, 1 1, and then we began to exclude them, and then we found that only1and 19 were left. At this time, I thought: one of these two numbers is the length of the common side of the front of the cuboid in the question; One is the front of the cuboid, divided by the sum of the lengths of the other side (both lengths are prime numbers).
So, I began to tell which number these two numbers were. The final result is 374 cubic centimeters.
My formula is: 209 =11*1919 = 2+1* 2 *17 = 374 (cubic centimeter). Later, after I solved this problem, I was happier than anyone else.
I also understand the truth that mathematics is full of mysteries, waiting for us to explore. Math diary, February, Sunday, this evening, I saw a puzzling math problem. The topic is: 37 students want to cross the river. There is an empty boat at the ferry that can only take five people. How many times must they cross the river with this boat? Careless people often ignore the "empty boat", that is, forget to have a gondola, so they can only take four people at a time.
In this way, 37 people subtract one rowing classmate, leaving 36 students, 36 divided by 4 equals 9, and the classmate who worked as a boatman on the other side for the last time also landed 4, so it takes at least 9 trips. On Sunday night in March, math diary, I saw a difficult problem in the Olympiad Book: the number of apple trees in the orchard is three times that of pear trees. Master Lao Wang fertilizes 50 apple trees and 20 pear trees every day. A few days later, all the pear trees were fertilized, but the remaining 80 apple trees were not fertilized.
Excuse me: How many apple trees and pear trees are there in the orchard? I am not intimidated by this question, but it can stimulate my interest. I think the apple tree is three times as big as the pear tree. If two kinds of trees are to be fertilized on the same day, Master Lao Wang will fertilize "20*3" apple trees and 20 pear trees every day.
In fact, he only fertilizes 50 apple trees every day, which is 10, and the last 80 trees. Therefore, Master Lao Wang has been fertilizing for 8 days. 20 pear trees a day, 8 days is 160 pear trees. According to the first condition, there are 480 apple trees.
This is to solve the problem with the idea of hypothesis, so I think the hypothesis method is really a good way to solve the problem. Math diary, April, Sunday Today, I met another math problem, and it took me a lot of effort to solve it.
The topic is: there are 30 birds in two trees, and 4 birds fly away from the second tree first. At this time, tree A flew to tree B with three birds, and the birds on the two trees were just equal. How many birds are there in each tree? As soon as I saw the topic, I knew it was a reduction problem, so I solved it by the method of reduction problem.
But when I checked, I found something was wrong. I will do it again more seriously.
I think there are as many as four missing, half of them are 13, and the restored B-tree is14; A tree is 16. The formula is: (30-4) ÷ 2 = 13 (only); 13-3+4 =14 (only); 30- 14 = 16 (only).
The answers are: a tree 16 and b tree 14. By solving this problem, I understand that no matter what I do, I should be careful, otherwise, even if I master the solution to the problem, the result will be wrong.
1) Today, my family went to KFC in Longgang to have a family fun. When we get there, people are always crowded. We finally ordered good food and found a seat to sit down.
Here comes the food. This is a sumptuous set meal. There are 12 drumsticks in it. I thought: how to divide it equally? Then I remembered the division of 12÷3=4.
We each have four drumsticks. Later, I ate my mother's 1 chicken leg and my aunt's two chicken legs. My aunt said, "You can't eat this for free. I ask you, how much did you eat? " How many more servings do you have to eat before you can finish them all? "I thought about it and replied," I ate 7/ 12, and then I ate 5/ 12. I ate all of it. "Fortunately, I learned the knowledge of fractions and can answer the questions correctly. (2) Today, my mother gave me 10 yuan to go shopping in the supermarket.
I bought a string of firecrackers 2/ 10, four lollipops/10, seven balloons 2/ 10, and finally a comb 4/ 10, a *. There is still one yuan left, and I have to pay it back to my mother.
When I got home, my mother ate 1/4 lollipops, my father ate 1/4 lollipops, I ate 1/4 lollipops, and I gave the other one to my brother Xiao Qiang next door. (Author: Xiao Enling) (3) Last week, we learned the scores.
Fractions have numerator, denominator and fractional line, for example, 1/3, where 3 is denominator, 1 is numerator and the middle horizontal line is fractional line. Scores are used in many places in life. For example, a book has thirty pages, and each page is 1/30 of a book.
Fractions can also be used to add and subtract! For example, half plus half equals two, which is 1. Why is this happening? If you divide a cake into two parts, each part is 1/2 of the cake, and then put the two parts together, there are two parts 1/2, which is just a cake.
When adding and subtracting fractions, if the denominator is the same, only the numerator is added, regardless of the denominator. And 2/2 of the numerator and denominator are the same, which is 1.
I also learned to compare the size of fractions. The teacher taught us the formula: numerator is the same as denominator, the fraction with large denominator is small, and the fraction with small denominator is large; Denominators are the same as numerators, with large numerator scores larger and small numerator scores smaller. The teacher also reminded us that when writing scores, we usually write the fractional line first, indicating the average score, then the denominator and finally the numerator. Math diary February Sunday Weather: Sunny Mood: Happy Today, our whole school is going to fall.
5. How to write math diary in Senior One can be divided into four parts: The first part is review, summarizing what you learned in the class that day to familiarize yourself.
The second part is preview, preview tomorrow's content. Read the contents of the book first, look at the strokes, and then write down your understanding and summary of the key contents in the book.
At the same time, you can do the questions in volumes A and B to check the effect of preview. The third part is self-practice, mainly doing some questions with strong improvement or thinking, generally doing 1-2 questions, one is the content learned today and the other is the content previewed.
I suggest you try to solve more than one problem and try to think about whether there is a simpler way. It is easier to deduct points if you do something wrong in the exam (I have suffered this loss). When doing improvement questions, we must pay attention to quality rather than quantity.
But those basic questions must be practiced more. The fourth part is evaluation, which is a story about mathematics learning mood. You can write about the gains in class, your thoughts and ideas about mathematics, and record your own trends, attitudes, ideas and happiness about mathematics learning at any time.
I believe you will like math! In fact, it is because I have done a lot of math problems that I have summed up my experience and found the fun of learning math. In addition, I also suggest that you sum up the reasons for your mistakes after the exam, and think carefully about where and why you made mistakes, so as to remind yourself before the exam in the future.
That's what I do. I find it very helpful. Some of the above are my own experiences, and some are excerpted from newspapers. I hope these are helpful to you.
6. What did math diary write 1? You can write about the use of mathematics in your life. Today is the weekend. In the afternoon, my grandparents and I went shopping.
We walked into the Jeanswest store, and grandma chose three T-shirts made in 29 yuan and bought them. Grandma asked me, "How much is this * * *?" Without thinking, I said, "A * * 87 yuan (29*3 is about 90,90-3 *1= 87 yuan)." After grandma bought clothes, we walked out of the clothing store.
Grandma said, "It's already half past five. Let's eat rice noodles. " Into the rice noodle shop, we bought a bowl of medium rice noodles, two bowls of small portions, a steamed dumpling and two bowls of porridge.
Grandma asked me, "How much should I pay?" I said, "A portion of * * 17 yuan is 4.50 yuan for a medium portion, 3.50 yuan for a small portion, 3.50 yuan for steamed dumplings, and 0 yuan for porridge/kloc-0 (4.50+3.5 * 3+1 * 2 =17 yuan). After dinner, we went home.
Buying oranges in life, there is mathematics everywhere. For example: buy food! Buy stationery! Measuring cloth, etc. , all need to use mathematics.
This semester, the teacher taught a new knowledge, that is, the multiplication and division of decimals. This knowledge helps me a lot! Last night, my mother went to buy oranges together.
A kilo of oranges 1.8 yuan. My mother bought 4.5 kg and should pay 8. 1 yuan. But the clerk was careless and didn't know how to calculate it, so it became 9 yuan money.
Fortunately, I used the knowledge of Protestantism this semester and calculated in my mind that 1.8/2=9 (angle) 1.8x4=7.2 (yuan) 9jiao +7.2 yuan =8. 1 yuan, which immediately corrected the clerk's mistake. Not only did my aunt, the shop assistant, praise me for my cleverness and my ability to multiply and divide decimals in such a small city, but my mother also praised me for saving her 0.9 yuan on the way home, and the knowledge I learned can be applied in my life.
Yes! If you don't learn this math well, you will lose not only 0.9 yuan, but also hundreds, thousands or even hundreds of millions. When can the snail climb out of the well? Today, I read a thinking question in a book: A snail was trapped in a well, the depth of which was15m. Snails climb 1 m every day and drop 30 cm at midnight. When can the snail climb out of the well? I listed the formulas on the draft paper: snail climbs 100-30 = 70cm every day, snail climbs 70 * 10 = 700 cm every day, snail climbs 70 * 20 = 1400cm every 20 days, leaving/kloc.
It takes 20+ 1=2 1 day for a snail to climb out of the well. It turns out that there is mathematics everywhere in life! What is sunny math on Sunday, September 9? Today, I heard my grandmother tell a story.
This is the true story of the famous Polish mathematician Selma Pinski. One day, he was moving, and his wife took out his luggage and said to him, "I'll call a taxi, and you look after the luggage here, *** 10 box."
After a while, his wife came back. He said to her, "Just now you said there were 10 boxes, but I counted only nine." "No, it must be 10."
"What to say, I'll count it again, 0, 1, 2, 3.
"
Oh, I see. Mathematics is composed of 0, 1, 2, 3, 4, 5, 6, 7, 8, 9. Understanding the corner on September 9, 2007 In our life, we can touch things related to mathematics everywhere.
Take the horn as an example. As long as you look closely, you can find many things related to horns. For example, the clock we often see, at noon 12: 30, I found a flat angle on the clock face. If you use 10 minutes again, an obtuse angle will appear. If we wait another 5 minutes, that is, 12: 45, a right angle will appear.
When the pointer is walking for 15 minutes, that is, 1, an acute angle will appear on the clock face. I listened and read, and my heart was full of joy. I want to learn math well and apply what I have learned to my present life.
The story of the decimal point Although the head of the decimal point is very small, I know that the decimal point plays a big role. For example, 3.80 yuan, without a decimal point, doesn't it become 380 yuan? 3.80 yuan is too different from 380 yuan! Don't you see how big the decimal point is in this comparison? Many students often miss it when writing, so this number is not what you originally wanted to write.
So let's not make this big mistake again! I ate sugar today, and my mother bought some sugar. I can't wait to eat two fifths first. Then, I took a sip of water and went to do my homework. After finishing the Chinese preview homework and math exercise book, I ate another fifth. Then my mother said, "What sugar is so greedy?" I want some, too. In this way, we ate four-fifths of the sugar, and my mother asked me, "How much sugar is left?" I replied, "Only one fifth of the sugar! "On this day, I expressed the sugar we ate with mathematical knowledge. I am really happy now.
7. A short math diary wrote 3 1 1. Today, my family went to KFC for a family meal.
When we get there, people are always crowded. We finally ordered good food and found a seat to sit down. Here comes the food. This is a sumptuous set meal. There are 12 drumsticks in it. I thought: how to divide it equally? Then I remembered the division of 12÷3=4. We each have four drumsticks. Later, I ate my mother's 1 chicken leg and my aunt's two chicken legs. My aunt said, "You can't eat this for free. I ask you, how much did you eat? " How many more servings do you have to eat before you can finish them all? "I thought about it and replied," I ate 7/ 12, and then I ate 5/ 12. I ate all of it. "Fortunately, I learned the knowledge of fractions and can answer the questions correctly.
Today, my mother gave me 10 yuan to go shopping in the supermarket. I bought a string of firecrackers 2/ 10, four lollipops/10, seven balloons 2/ 10, and finally a comb 4/ 10, a *. There is still one yuan left, and I have to pay it back to my mother.
8. Write an article about math diary Today, when I came home from school, I suddenly saw many people in front of a shop.
When I took a closer look, it turned out that the store was engaged in promotional activities. You can answer a question by paying one yuan. If you can answer correctly within 30 seconds, you will win the 30 yuan. I saw others losing one after another, and I thought, What's so hard about it? I paid one yuan out of curiosity.
I followed my boss into the store, and he began to ask, "Xiaoming went to the bookstore to buy books, and bought 17 books with 99 yuan money. How much did he spend? " As soon as he finished, he showed a sly look and began to time. As time went on, my sweat dripped down. How to calculate this 99 times 17 without vertical calculation? At this moment, it dawned on me. There is a page in "Daily Practice of Oral Calculations" that says otherwise: The quick calculation method of multiplying a number within 100 by 99 is to multiply this number by 100 first, and then subtract this number.
Thinking of this, I blurted out: "1683." As soon as I finished, the boss almost fell to the ground. He looked at the timer for only 28 seconds and gave me the money helplessly.
I walked out of the store with 30 yuan and looked at the envious eyes of others, not to mention how happy I was. At this time, I thought: Mathematics is not only the calculation of 1+ 1, but also has a wide range of uses in life. Besides, math is used for shopping and other things.
So, I want to say it again, "Mathematics is really useful." .
9. Write an article about math diary Today, when I came home from school, I suddenly saw many people in front of a shop.
When I took a closer look, it turned out that the store was engaged in promotional activities. You can answer a question by paying one yuan. If you can answer correctly within 30 seconds, you will win the 30 yuan. I saw others losing one after another, and I thought, What's so hard about it? I paid one yuan out of curiosity.
I followed my boss into the store, and he began to ask, "Xiaoming went to the bookstore to buy books, and bought 17 books with 99 yuan money. How much did he spend? " As soon as he finished, he showed a sly look and began to time. As time went on, my sweat dripped down. How to calculate this 99 times 17 without vertical calculation? At this moment, it dawned on me. There is a page in "Daily Practice of Oral Calculations" that says otherwise: The quick calculation method of multiplying a number within 100 by 99 is to multiply this number by 100 first, and then subtract this number.
Thinking of this, I blurted out the second method: "1683." As soon as I finished, the boss almost fell to the ground. He looked at the timer for only 28 seconds and gave me the money helplessly.
I walked out of the store with 30 yuan and looked at the envious eyes of others, not to mention how happy I was. At this time, I thought: Mathematics is not only the calculation of 1+ 1, but also has a wide range of uses in life. Besides, math is used for shopping and other things.
So, I want to say it again, "Mathematics is really useful." .
10. Math Composition 400 words Today, because my parents are at work, my mother sent me to Xinhua Bookstore, which is crowded.
As soon as I entered the door, a hot air came to my face. This lively scene made me suddenly impulsive. The bookshelves are crowded with people. If you want to see clearly, you have to squeeze in.
I used to be so "civilized" that I forgot any courtesy. I exploited every loophole. I completely ignored the pressure from behind and chose books at will.
After a while, I finally chose the book I read. Squeezing out of the crowd, I found one who looked like a teacher holding a lot of books.
I asked the teacher politely, do you need any help? The teacher readily agreed. Teacher, are you choosing books for your students? Yes! How many students are there in your class? The teacher didn't tell me directly, but asked me, let me guess.
There are 6 copies per person, leaving 4 1 copy, and 8 copies per person are short of 29 copies. How many students are there? How many books? This time, I was stumped. I thought about it and suddenly had an idea. The two points are different, resulting in a difference of 4 1+29=70 (books). Everyone divides six books into eight, and the difference is 8-6 = 2 (books).
Oh! Suddenly, I understood that the total difference is known, and the difference between everyone is also known. Isn't that the total number? I quickly found out that there were 35 students, and when the number of students was found out, the books were easier to find. 6*35+4 1=25 1 (Ben) I told my teacher the answer, and the teacher said, "You are great! Exactly! " In fact, mathematics is quite interesting, especially when you get the correct answer through hard work. The beauty in your heart is really unspeakable! In the future, I will explore and discover in the castle of mathematics and constantly experience the happiness brought by success.