Math Story (1)

* * On June+10, 5438, Guo Meng, a 20-year-old Shenyang girl studying in the Department of Mathematics at the University of Illinois at Urbana-Champaign, was named "the best girl in mathematics in the United States". This selection is conducted once a year in the United States, with only three or four places each time. As the best student, Guo Meng's name will be engraved on the wall of the main library of Urbana-Champaign, which is the first time that China students have won this honor in the United States.

At the same time, Harvard University, Massachusetts Institute of Technology, Stanford University, Massachusetts Institute of Technology, Columbia University, University of Chicago, Yale University and more than a dozen other famous American universities have sent her doctoral admission notices. Harvard University also promised her that tuition fees would be free and that she would provide $30,000 in living expenses every year.

Guo Meng, a sunny and beautiful post-90s China girl, has attracted wide attention from all walks of life in the United States with her excellent academic performance, and has become an example for American teenagers to learn.

199 1 March, Guo Meng was born in Shenyang. Since childhood, she has developed a strong interest in mathematics. Traveling in the kingdom of mathematics, she feels very happy and happy. She seems to see what heaven looks like: beautiful and fragrant.

After school, Guo Meng never attended any extra-curricular cram school, nor did he attend the Olympic Mathematics class. Everything is carried out according to his own interest in learning. She is willing to study exercises and has a persistent spirit. A topic often has different solutions, flexible learning methods, and efforts in understanding.

Guo Meng is willing to study hard and study hard, and also has a very outstanding performance in style. Her violin solo has been performed in school many times, and the flowing piano sound is exquisite, graceful and melodious, which has left a very unforgettable impression on everyone. She likes calligraphy and has high attainments. Her works have won many awards. Her spoken English is very fluent and pure. Foreigners visit the school, and she is accompanied by an interpreter all the time; She is also the host of the school, and her youthful and lively hosting style often appears in school meetings. ...

Guo Meng's parents both graduated from the Mathematics Department of Harbin Institute of Technology. In her study, her parents never care about her ranking in the class. The key is to make her understand the topic. In the eyes of parents, an exam is not ideal and does not mean anything. What is more important is to cultivate and exercise children's learning ability, understanding ability and thinking ability. Under the guidance of this persuasion, Guo Meng is very good at thinking, looking for ways, studying very consciously, and never worrying about his parents.

In 2004, Guo Meng won the first prize in the "Star of Hope" mathematics competition for middle school students in Liaoning Province. In 2005, he won the second prize in the national high school mathematics competition. The achievement of this series of excellent results has given Guo Meng endless interest and happiness in learning, and she is moving towards a higher goal.

In 2007, Guo Meng took the American College Entrance Examination; In 2008, she was admitted to several American universities. She finally chose the Department of Mathematics of the University of Illinois at Urbana-Champaign, where Hua, a famous mathematician in China, once worked.

Interesting Mathematical Problems (2)

1. Three people went to a hotel and stayed in three rooms. Each room costs 10 yuan, so they pay the boss 30 yuan. The next day, the boss said that there were enough rooms in 25 yuan and asked my brother to return them to three guests, 5 yuan. Who knows, my brother was greedy, only gave everyone a refund of 1 yuan, and secretly took 2 yuan himself. This is equivalent to three guests each spent nine dollars, so three people spent a * * * 27 dollars, plus little brother took no 2 dollars, a total of * * * 29 dollars. But at the beginning, all three of them gave their lives 30 yuan. What about 1 yuan?

2. Two rings with radii of 1 and 2 respectively. The small circle revolves around the circle of the big circle in the big circle. How many times did the small circle turn? If you go around the outside of the big circle, how many times does the small circle turn? How to choose sampling method

In order to make the people in Yushu earthquake-stricken area rebuild their homes as soon as possible, the Youth League Committee of the school called on all the students 1200 to carry out the donation activity of "Love Yushu, Love Boundless" for earthquake relief. In order to keep abreast of students' donations, the Youth League Committee plans to select 60 students from the whole school for investigation, but the Youth League Committee has three opinions on the sampling method.

The propaganda committee member said, "Because I am in Class 7 (3), I am familiar with the seventh grade students, so I will simply randomly select 60 students from our seventh grade students for investigation."

Members of the organizing Committee said: "I am a girl and know more about girls. Let's take 60 students from girls by simple random sampling. "

Deputy Secretary of the Communist Youth League Committee said: "I think it is more reasonable to select 60 students from the whole school by simple random sampling."

Finally, they had to go to the secretary of the Youth League Committee, and he decided on the best plan.

After listening to their respective sampling schemes, the secretary of the Youth League Committee patiently helped them analyze and said: "Scheme 1 does not meet the sampling requirements because it is only drawn from seventh grade students and does not reflect the donations of other grade students; Scheme 2, only selected from the specific group of girls, does not reflect the donation of boys and does not meet the sampling requirements; Scheme 3: Through a simple random sampling of the whole school students, we can estimate the donation of the whole school students. Compared with scheme 1 and scheme 2, scheme 3 can reflect the donation of the whole school students. Therefore, we should choose option three to implement. "

Mathematics learning method (3)

The usual mathematical research:

1, preview carefully before class. The purpose of preview is to listen to the teacher better. Through preview, the mastery level should reach 80%. Listen to the teacher answer these questions with questions that you don't understand in the preview. Preview can also improve the overall class efficiency. Specific preview method: finish the topics in the book and draw the knowledge points. The whole process lasts about 15-20 minutes. If time permits, you can also finish your homework.

2. The combination of mathematics learning and practice. It's no use just listening in math class. When the teacher asks the students to do calculations on the blackboard, they should also practice on the draft paper. You must ask questions you don't understand, and you can't help asking for solutions. () Otherwise, if you encounter similar problems, you may not take the exam. When listening to the teacher's lecture, you must concentrate on the details, otherwise, "the embankment of a thousand miles will collapse in the ant nest."

3. Review in time after class. After finishing your homework, sort out what the teacher said that day, and you can do extracurricular problems for about 25 minutes. You can choose the extracurricular books that suit you according to your own needs. The content of the extracurricular problem is probably today's class.

4. Unit test is to detect the recent learning situation. In fact, the score represents your past. The key is to summarize and draw lessons from each exam so that you can do better in the mid-term and final exams. Teachers often take exams without notice and review them in time after class.

Math Examination Skills (4)

If you want to get high marks, you can't lose points in choosing topics, filling in the blanks and calculating problems. You can't be distracted during the math exam, and you can't think, "What if you don't do well in the exam?" In general, the final exam questions are those you don't know how to do, but you may suddenly understand. When you encounter such a problem, you should be calm and analyze it with all the conditions given to you. For example, there are two blank clocks in this exam, and there are several fill-in-the-blank questions at the end of last year's seventh grade. These conditions are of great help to your problem solving. There is plenty of time for mid-term and final exams, so we should slow down, not as soon as possible, and strive for a success. Set aside about 35 minutes to check.

Finally, I would like to remind you that doing more questions has a certain effect, but it is most important to attend classes, answer questions carefully, improve accuracy and sum up experience. We should also apply what we have learned to our lives, so as to apply what we have learned. When you use mathematical knowledge to solve practical problems in life, you will feel the joy of learning mathematics.

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