From small town academic to chief scientist

It wasn't until ten o'clock in the evening, when the library was about to close, that Zhou Yi was woken up from the sea of ​​books by the library staff.

Zhou Yi looked around. Apart from the staff, Xia Xue was here.

"Why are you still here?"

Zhou Yi asked with some confusion.

"Study duck, our major also has a lot of books to read, and many books that are not covered in textbooks also need to be read. Senior, you are working so hard, I can't fall behind."

Xia Xue blinked her smart eyes and said sweetly.

The staff on the side said:

"Okay, okay, it's closed. Come back tomorrow."

Only then did Zhou Yi and Xia Xue leave the library.

"I'm going back to the dormitory first."

Zhou Yi left a word and ran away directly. This Xia Xue's purpose is impure. I must not let a woman ruin my Taoist heart!

If you are not a master of mathematics, you must not lose your Taoist mind.

Xia Xue looked at Zhou Yi who was running away, a smile appeared on the corner of his mouth, and then he quickly walked to the dormitory.

Zhou Yi returned to the dormitory. After washing up very quickly, he continued to read.

Luo Yun and Yang Shuai were also busy with their own affairs.

Luo Yun was busy with things in the class, and Yang Shuai was busy coding.

As for what happened in the large group during the day, everyone tacitly agreed not to mention it.

From one o'clock in the afternoon to ten o'clock in the evening, except for half an hour for dinner, Zhou Yi stayed in the library and never went out.

From domestic mathematics textbooks, we can see the foreign textbook "Vladimir A. Zorich Mathematical Analysis", from domestic analytic geometry textbooks, we can also see foreign textbooks.

There are only two different foreign advanced algebra textbooks left.

Zhou Yi originally wanted to study domestic textbooks to complete the tasks, but thinking that this would lay a solid foundation, he took the initiative to choose foreign textbooks with a higher degree of difficulty.

If you want to build a tall building, the foundation must be solid.

I watched until two o'clock in the morning, and most of the book "Book of Changes" was still unread.

Thinking that there would be classes the next day, I fell asleep.

At six o'clock the next day, Zhou Yi got up and washed himself.

Then I bought two steamed buns and hurried outside the library to start memorizing English.

"It takes about three days of memorizing English to fully master the language."

Zhou Yi murmured.

I have gained 200% comprehension since yesterday, and I have almost a photographic memory for writing subjects.

In addition to the subject of English, it is very simple compared to science.

I carry it for two hours every morning, which is about the same amount of time for three days.

Teaching Building 3301, School of Mathematics.

"Lao Zhou, here, here."

Yang Shuai saw Zhou Yi entering the classroom and shouted loudly.

After Zhou Yi walked over and sat down, he heard Xu Zihan, the first in the class, say:

"The first lesson is about counting fractions, but it's not Teacher Ma who teaches us fractions, but Professor Tang."

The boy next to him, who was third in the class, said:

"I know it's him, but I heard that this professor is a bit ruthless. He lectures very quickly in class. Some theorems that are not proved in the book are even given to students as homework."

“Isn’t it possible that the equivalent theorem of the gathering point theorem could become our homework?”

"Hey, you're still previewing? You deserve to be number one in terms of grade point. You have something."

"I've previewed it, but I don't know how to prove it. It's hard to count the points."

Xu Zihan complained.

Many people around were whispering and discussing matters related to study.

The completeness of real numbers is the most difficult part of counting fractions, and it is normal for many people to be afraid of it.

Many people don’t even understand it.

Not long after, under the eyes of everyone, the old professor walked into the classroom and started teaching the first class.

Originally, Tang Ping wanted to find trouble with a 20th-level student named Zhou Yi, but he was busy with various things and was delayed again, and he didn't know which class this Zhou Yi was from.

Then he shook his head and started class.

"In fact, a multivariate function is the generalization of a univariate function. It retains many properties of a univariate function, but due to the increase from one variable to multiple variables, it has produced many new properties. We need to have a new understanding of these properties. "

The old professor said slowly, and the PPT was flipped page by page.

"If the domain of a function of one variable is the set of points on the real axis, then the domain of a function of two variables is the set of points on the coordinate plane."

The class progressed slowly, and many people felt drowsy after listening to it. The previous points were okay and easy to understand, but when it came to completeness and proof of theorems,

Everyone was impatient and distracted.

Moreover, the professor spoke very quickly, and although he spoke very thoroughly, very few people could follow him.

"Let me give you the equivalent theorem of the gathering point theorem. There is no proof in the book, and I don't want to prove it for you. I'll leave it as homework and hand it in.

The finite covering theorem is also similar to the proof process of one element. You are all top students of Chongqing University. These are not difficult for you, so you should hand them in as homework. "

When Professor Tang saw that the lectures were almost complete, he began to assign homework.

"Or if someone proves any question on the blackboard right now, I can consider adding 10 points to the normal score in the final assessment."

Countless people in a class were silent, who would do this?

No. 1 Xu Zihan doesn't know how to do it, let alone them.

You can only prove it by searching for information or thinking more about it. Who can figure it out right away in such a short time in class?

Zhao Lili wanted to go, but she couldn't, and neither did the study committee members. No one said anything.

Xu Zihan also wanted to give it a try. It was related to the final results and even grade points. One step should be taken first, and every step should be taken first.

But neither can Xu Zihan.

"Is there no one? Then you will miss the opportunity to add points."

At this time, Zhou Yi raised his hand and said:

"Professor Tang, I can."

"Huh? Which question do you know?"

Tang Ping didn't expect that anyone would know it. It seemed that some students had previewed in advance.

The students in the classroom also looked at Zhou Yi in surprise, he could actually?

Would a mere tenth place do this?

Yesterday, someone said that Zhou Yi had some energy. Now it seems that it is true?

Zhou Yi said calmly:

"Everyone can do it. Do you think I'll get 20 extra points?"

"Both? They will give you 20 points."

Professor Tang glanced at Zhou Yi and found that it looked familiar, but he still said firmly.

Not long after, Zhou Yi stepped onto the podium under the gaze of everyone, picked up the chalk, and began to write the process of solving the problem.

The first question is the question originally read by Zhou Yi.

The bounded infinite point sequence {Pn} contained in R must have a convergent subsequence {Pnk}.

At that time, Zhou Yi could deduce the writing on the blackboard in his mind, let alone now that he has thoroughly understood several textbooks.

After a while, the only sound in the entire classroom was the sound of Zhouyi chalk writing.

Everyone present, Yang Shuai, was shocked, some classmates who were watching the show were shocked, and those who just thought Zhou Yi had a mental problem were also shocked.

You, Zhou Yi, have become so strong without saying a word.

Xu Zihan suddenly felt a sense of crisis, and his number one position was in jeopardy.

Zhou Yi's math level is actually about the same as him. The reason why Zhou Yi ranks first in grade point is because Zhou Yi has low grade points in other subjects and uses the time he spent on those subjects to work part-time.

Otherwise, how could I buy a computer?

In fact, there are too many ways to prove this theorem, and Zhou Yi has three or four kinds that come to mind right now.

The simplest is the analogy of one-dimensional bounded sequence proof,

Using the Bolzano-Weierstrass theorem of R1, we get the convergent subsequence {xm} of {xn}, and then examine the subsequence of {ym}, and there is also a convergent subsequence {yk}, so we get that {(xk, yk)} is {pn} Converging subcolumn.

Of course, you can also use the closed domain theorem you learned today to prove it. There are many methods.

Zhouyi casually wrote the simplest one on the blackboard.

Then, with everyone's surprised eyes, the proof of the second question began.

Proof of finite covering theorem.

There are too many methods. Zhou Yi wrote down one of them casually, and then respectfully said to Professor Tang Ping:

"Professor Tang, I have finished writing."

After Tang Ping read it, he praised without hesitation:

"Yes, the basic skills are good. There is no redundant mathematical language and no redundant steps. I didn't expect that there is a seedling in Class 1 of grade 20 who has good basic skills. What is your name?"

"My name is Zhou Yi."

"Well, are you Zhou Yi?"

Tang Ping was a little surprised, and his face looked in disbelief.