National Top Stream

Pierce shook his head, and said helplessly, "I'm still going through the formalities, and it probably won't be until October, but I've already settled down at Dragon City University."

"It's just right." Zhuang Weiran is very familiar with Pierce. Today is the first time he officially lectures to students as a professor of Dragon City University, and Pierce just happens to be his assistant professor.Before Pierce understood anything, he was led to the office by Zhuang Weiran, "Today is my first day of class. It just so happens that Mr. Pierce, as my assistant, will go to class with me."

Pierce nodded lightly, "Professor, what are you going to teach today?"

"Linear algebra." Zhuang Weiran sat on the seat, "It's relatively simple."

That is indeed relatively simple. Pierce thought about it, and Zhuang Weiran began to say again, "Mr. Pierce, I personally suggest that since you are a doctoral student in China, it is better to learn Chinese, what do you think?"

"I have signed up for a Chinese training class, but I'm not sure when I can learn it." Pierce smiled wryly. In his opinion, Chinese is really too difficult.

He didn't understand many things at all. Before he wanted to go to Huaguo to study mathematics with Zhuang Weiran, he had planned this.After all, Huaguo doesn't speak English, and he will stay in Huaguo for so many years, so he definitely needs to learn Chinese.

After arriving in China, he signed up for the Chinese class, and he has been in the Chinese class for the past few days.

After Zhuang Weiran packed up his things, he helped to leave the office with the things.When I came to the classroom, almost all the students had already arrived in the classroom, and many domestic and foreign professors were sitting on the chairs. Because it is a large classroom, hundreds of people can be seated.There are not so many students, there are only more than 100 people, but the professors have dozens of seats.

Zhuang Weiran put the textbook on the desk of the podium, and then said, "Let me introduce first, my assistant Pierce, he will most likely be your senior brother in the future, he is studying for a Ph.D. at Princeton University, and now he is transferring to Dragon City University."

"My name is Zhuang Weiran." Holding a pen, he glanced at the students below. The students who were afraid to speak because there were so many professors sitting there were even more shocked when they saw Zhuang Weiran. Majestic, but dare not speak.

Everyone was cautious, some looked down at the book, and some looked up at the blackboard seriously.

"My phone number and email address." Zhuang Weiran began to write the phone number and email address on the blackboard, "I hope my phone number and email address will not be leaked out."

"Also, I don't need to introduce myself too much, do I?"

No one spoke. Indeed, Zhuang Weiran didn't need to introduce himself too much. As for his name, who else in Longcheng University doesn't know?

"Starting today, I will teach you linear algebra. Because this part is relatively simple, my speed is relatively fast. The explanation in class may not be particularly detailed. If you do not understand somewhere, you must come to my office after class Ask me." Zhuang Weiran paused for a moment, pretending that I don't think any of you dare to pretend to understand.

scare all the students.

"My office address is on the second floor of the office building of the Department of Mathematics." Zhuang Weiran continued to look at the students, "Remember, you must always ask me if you don't understand, whether it's by phone or email. But I Personal suggestion, you come to the office and ask me, I can explain to you in more detail. If I am not on a business trip or other things, I am usually in the office.”

"Also, let me say something first. I don't know how to call names. You won't fall in love with my class. Anyway, during the final exam, I will not show mercy to anyone. Don't worry, I will probably be the last student in Dragon City University to correct the papers. Strict teacher, no one." An evil smile appeared on his face, "Also, I won't give you the key points, as for the exam questions...it will be more difficult than you imagined. If I don't draw inferences from one instance, I personally I think it’s best for you to change departments, because I am not only your linear algebra teacher, but also many algebra, geometry and functional analysis in the future. Even if I am not here, Mr. Pierce will explain to you instead of me, I guess you It's also choking."

"Weigh it, whether you can pass the test. If not, there is still time to change departments."

"Principal Chen and Director Zhou are here, and those who want to transfer to another department should look for them after class." After Zhuang Weiran finished speaking, regardless of the shocked expressions of the students, he continued, "Linear algebra is a branch of mathematics. Its research object is Vector, vector space (or linear space), linear transformation and finite-dimensional linear equations. The theory of linear algebra has been generalized into operator theory. Since nonlinear models in scientific research can usually be approximated as linear models, Linear algebra is widely used in natural and social sciences. 1”

"So linear algebra is very important." Zhuang Weiran held a pen, "Study hard, don't learn well, don't say you are a student of the Mathematics Department of Longcheng University, especially when I teach you."

[Let's talk about linear equations first

……

From the perspective of linear equations, this situation corresponds to binary linear equations (2) having infinitely many solutions. According to the above theorem, the necessary and sufficient condition for linear equations to have infinitely many solutions is that the rank of the coefficient matrix of the equations is equal to The rank of its augmented matrix is ​​less than the number of unknowns in the system of equations

……

From the point of view of linear equations, this situation corresponds to binary linear equations (2) No solution According to the above theorem, the necessary and sufficient condition for the linear equations to have no solution is the rank of the coefficient matrix of the equations and its augmented matrix The ranks of are not equal, that is, the inverse form of the first clause of the theorem:

rank(a)≠rank(b)

……2】

Zhuang Weiran wrote on the blackboard, while Pierce stared at the students.I don't know if it's because of Pierce's more friendly appearance, many students are curiously looking at this Pierce who transferred from Princeton University to Dragon City University.It seemed that they were not afraid of him, but Zhuang Weiran's speed was so fast that they had almost covered Chapter 1 in one class, which gave them a lot of headaches.I haven't understood it at all, Zhuang Weiran's explanation can be regarded as simple and profound.Many professors nodded slightly. They didn't think the speed was too fast. They always felt that the students should be able to understand it.

But many students struggled and couldn't keep up with Zhuang Weiran's rhythm. There were many linear algebra courses this semester. According to Zhuang Weiran's explanation, it is estimated that Zhuang Weiran will be able to explain the entire linear algebra in October.

The students scratched their heads, they really didn't understand a lot of questions.Zhuang Weiran didn't stop until the bell rang. Looking at it, he had almost explained the contents of two chapters.At this speed, the students must not be able to keep up with the rhythm. Even if he had previewed it before, he still spoke too fast.If the students don't come to him, it is estimated that it will be impossible to pass the linear algebra test.

Especially since they are still in the Department of Mathematics, linear algebra will only be more difficult.

"get out of class is over." Zhuang Weiran turned around and left without staying for a second, and said as he walked, "Remember, you should ask me if you don't understand, if you don't come to ask me, I can only pretend that you all understand .”

The students sighed that before their college entrance examination, the teacher told them that they could play whatever they wanted after they got to university.Can this be played?I'm afraid the learning tasks are heavier than those in high school.At any rate, the high school teacher's explanations are more detailed. Even if the progress is fast, students who can be admitted to the Department of Mathematics of Longcheng University can understand it in advance.But Zhuang Weiran's class, even the person with the best college entrance examination scores present, sounds like a cloud.

The speed is too fast, and does not give people extra time.For Zhuang Weiran, these things seem to be what they should have been. If you don't know it, it must be that you have a problem, not him.

The professors also left, but none of the students went to tell President Chen or Director Zhou about changing departments.The Department of Mathematics and Department of Physics of Longcheng University are the majors with the highest marks, and then there is the medical school next door. If they want to go to medical school, they might as well continue to study mathematics and theoretical physics.

"Professor Zhuang's class is really too fast." A student couldn't help complaining, "I previewed a few days ago, I knew that Professor Zhuang's lecture speed would definitely be very fast, but I didn't expect it to be so fast .”

The students next to him also began to sigh, "Yes, with Professor Zhuang's progress, he can finish the course in October at most, and we won't be on vacation until January. Why do we have several months left?"

"Self-study, go to the office and ask Professor Zhuang. I didn't hear what Professor Zhuang said. I'm so sure that we must not understand in a class. We either ask him or study by ourselves. I choose to ask him... Although I know that I will definitely be rejected. He complained, but in order not to fail at the end of the semester, I'd better ask Professor Zhuang."

"Yes, there is no other way than to ask Professor Zhuang." The other students echoed the student who spoke just now, everyone looked at me and I looked at you and shook their heads.

Professor Zhuang's courses, although the professor explained in simple terms, there are still many details that they did not understand.

After Professor Feng left the classroom, he said to the people next to him, "Look at the man surnamed Zhuang, how proud he is. I don't think these students understand at all. If he continues like this, our Dragon City University Mathematics It’s no wonder the department is good. Also, what clothes are you wearing today? Knowing that there are so many professors from home and abroad attending the class, and standing on the podium in casual clothes, I thought it was some high school student who went to the wrong school. Really It's so disrespectful."

"Okay, Professor Feng." The person next to him comforted, "I have seen many scenes like this at Princeton University, and I also watched it. There is indeed nothing wrong with Professor Zhuang's lectures. The speed is a little faster, but He was at the same speed when he was at Princeton University. He also said that students can go to the office to find him if they don’t understand anything, and he will try his best to answer it.”

"Professor Zhuang is very serious and responsible." The person next to him sighed softly, "Professor Feng, I know you have opinions on Professor Zhuang, but any opinions are opinions. Professor Zhuang really has nothing in this regard. mistake."

"That's right." Professor Lin said with a smile beside him, "Professor Feng, if you have the ability, you will be the same as Professor Zhuang, and let so many professors come to the school to listen to his lectures."

"Hey, Professor Lin, you have slandered Zhuang Weiran more times than I have. I'm just complaining. I think Professor Lin wants to do something."

"What can I do? Professor Zhuang has a lot of face. How can I dare to compare with Professor Zhuang when there are so many mathematicians at the mathematician level for a mathematics award?" Professor Lin said sullenly and snorted. Turn around and leave.

"I don't think Professor Lin wants to do something?" The professor next to Professor Feng said softly, "Professor Lin has been dissatisfied with Professor Zhuang for a long time."

"Never mind." Professor Feng sneered, there were not a few people who wanted to attack Zhuang Weiran.Both at home and abroad, he can't even complain about Zhuang Weiran, and he can't do anything.He is jealous of Zhuang Weiran, but he is not a fool.For this kind of thing, it's fine to complain and get over your mouth.Going up to fight Zhuang Weiran, that's something a fool would do.

Zhuang Weiran's reputation alone is enough to destroy the reputation of these professors. If they really fight with Zhuang Weiran, no matter what kind of ring they are in, they will suffer in the end, not Zhuang Weiran.

What Professor Lin was thinking, Professor Feng didn't know, but he figured it out now.He just made Zhuang Weiran sour, and he didn't do anything else.

…………

Zhuang Weiran returned to the office, sat on a chair, continued to read graphene papers, and suddenly remembered what he had explained to Pierce a few days ago, "By the way, Mr. Pierce, I asked you to do a mathematical model of graphene a few days ago, you Have you started yet?"

"I'm doing it." Pierce felt that there was much more to do now than when he was at Princeton University.I also need to help Professor Zhuang make a mathematical model of graphene, learn Chinese, and research topics.He's so single-minded, he doesn't have time for parties or anything like that.If he has time to rest, he just wants to have a good sleep, and he doesn't want to think about other things.

"En." Zhuang Weiran continued to take notes, and after a while, some students trotted all the way to his office.

Looking at the immature student in front of him, he felt a sense of fear, and he poked his head and said to him, "Zhuang, Professor Zhuang, what you said today about the influence of the number n of unknowns on the solution of the equations, I still don't understand." I don't quite understand. Can you explain it to me again?"

He was ready to be sprayed or laughed at by Zhuang Weiran.

Zhuang Weiran nodded lightly, took a pen, and began to explain to the students, "The size of n reflects the size of the degree of freedom... On the contrary, it decreases. Let's give an example, if =n=2, then the equation represents two-dimensional geometry If the two straight lines on the plane are equal to 2, n increases to 3...then the possibility of the original two straight lines intersecting at one point will tend to increase. 3”

Looking at the student, he asked seriously, "Do you understand? If you don't understand, I will explain it to you again?"

"No, no, no need." The student hurriedly shook his head, "I, I just need to understand and understand when I go back. I understand everything you said, but there are still some details that I haven't fully understood. I can digest it when I go back. understand."

"That's good." Zhuang Weiran nodded lightly, "Go back to Aite and all of them in the class group, and tell them, remember to ask me any questions you don't understand."

"Thank you, Professor Zhuang." The student bowed sincerely to Zhuang Weiran and left.

Zhuang Weiran explained to him very seriously, and did not scold him.It seems that Professor Zhuang is not angry at everything.Probably, what Professor Zhuang said just now is not wrong. It is very normal for students to have many misunderstandings about the content of his class.So let them ask him what they don't understand, and he won't be angry.

Pierce was doing mathematical models by the side, and Zhuang Weiran didn't bother him.

After a while, several students came together.Probably because he was afraid of taking Zhuang Weiran's magical damage alone, and wanted to find a few people to share the damage.

Zhuang Weiran finished explaining to the students with a smile, and there was no such serious scene on TV at all.While many students breathed a sigh of relief, they began to discuss whether Professor Zhuang's seriousness on TV was a human design?

But I heard that Professor Zhuang was like this when he was at Princeton University.Why is it that after returning to China, it seems that there is no such thing as lecturing to the students.

Probably they didn't know, because it was the first time to give a lecture, Zhuang Weiran knew that his speed was too fast, the students didn't understand, and it was easy to understand if there were problems.But in the future they still don't preview, and they come to ask him basic questions.Then he must have yelled at the students before he began to explain to the students.

This is probably the so-called novice benefit.

After eight o'clock in the evening, some students came to the office to ask him, but Zhuang Weiran didn't even have time to eat dinner.He Ruiming and He Zhenguo are still working overtime.Zhuang Weiran explained until ten o'clock in the evening, and his stomach kept growling. After the students left, he touched his shriveled stomach, and Zhuang Weiran sighed.Pierce next to him has had dinner, "Mr. Pierce, do you need some supper?"

Originally Pierce wanted to bring back some food for Zhuang Weiran, but Zhuang Weiran disliked that eating would reduce the efficiency of teaching students, so he didn't let him bring it.

At this time, probably only the restaurant outside Longcheng University still has something to eat.

"Let's go, Mr. Pierce, I'll treat you to dinner tonight." The weather is getting cooler, it's okay to wear short sleeves during the day, but it's easy to catch cold if you only wear short sleeves at night.Zhuang Weiran took the coat and put it on her body, and turned off the lights in the office.Leaving the office, it was deserted, almost no one was in the office.

He was probably the only professor giving lectures to the students so late today. As soon as he left the lobby of the office building and walked out the door, the security guard ran up and asked, "Professor, is there anyone else in the building?"

"This... I'm not sure." Zhuang Weiran shook his head. He was on the second floor, and the entire office building had seven or eight floors. He didn't know if there were professors on other floors.

"Hey, then I'll go up and have a look." The security guard and Zhuang Weiran left after talking, and Zhuang Weiran gave Pierce a look next to him, "Let's go, Mr. Pierce, have you ever eaten outside the school?"

Pierce shook his head honestly, "I don't have time recently, and I haven't eaten outside of school."

Leaving the main entrance of Longcheng University, there are still many students coming in and out in front of the gate.The outside is very bustling and lively. Because there are several universities in this area, not only Dragon City University, but also several universities are all around, so this area is one of the most prosperous places in Dragon City all year round.

Because of the large number of students and the high flow of people, many catering industries and even shopping malls are built nearby.There are snack streets, shopping malls, and many facades here. The lights are extremely bright, and there are many young people coming and going.

Zhuang Weiran walked to the food stall beside him. Although there were only two of them, he had to reward himself for eating so late.

Before entering the gate, I heard the laughter from the students inside.