Chapter 298： The shock of Professor Li Yong

"I am the president of the university (

The Haiyun Campus of Ludao University, also known as Haiyun Garden, is only separated from the main campus by a Furong tunnel. The three colleges of the School of Mathematical Sciences, the School of Information Science and Technology, and the School of Software are located here.

Haiyun Teaching Building 204.

The classroom was quiet, except for the screeching of chalk rubbing against the blackboard.

"Suppose X1, X2,...Xn, Xn+1 are taken from a sample of the population X obeying n(μ, σ2), X=12∑xi, Sn2=1n∑(Xi-X)2, find Xn+1Sn√ The distribution of n-1n+1."

Professor Li Yong removed the dust from his hands, and faced the 51 students who were sitting at risk.

The math majors sitting below looked up at the questions on the blackboard, some fell into contemplation, some scratched their heads, and some looked blankly and then buried their heads.

emmm...

What the **** is this written about?

High school mathematics is different from college mathematics. The former is mainly based on calculation, while the latter is mostly proof.

Then the interesting thing is that the high school teacher said that you will learn when you go to college, and the college teacher defaulted to saying that in high school...

Li Yong looked around and noticed the expression of Lu Zhou sitting in the first row. He moved in his heart and asked Lu Zhou, "Can you do this question?"

"Yes." Lu Zhou raised his glasses and nodded.

"Then come up and write down the answering process." Li Yong smiled slightly, just to test Lu Zhou's mathematics level.

"good."

Lu Zhou stood up, walked directly to the podium, picked up the white chalk and started writing.

"X(n+1)~N(μ,σ2), X~N(μ,σ2n), independent of each other, X(n+1)-X~N(0, (n+1)n*σ2).

√[n(n+1)]σ*[X(n+1)-X]~N(0,1).

nS2σ2~χ2(n-1).

These two are independent, the proof is slightly......

Let X~N(0,1), Y~χ^2(n), and X and Y are independent, then T=X√(Yn)~t(n)…………

From the definition of the t distribution above, ~t(n-1) is known. "

The expressions on the faces of the students under the stage changed from dazed to suddenly enlightened, while Professor Li Yong on the side flashed a hint of joy in his eyes.

After Lu Zhou answered the question, he returned to his seat without saying a word.

Professor Li Yong stepped onto the podium with a smile on his face, and praised Chen Hao: "Student Lu Zhou's answering process is perfect, even if I do it, it is almost the result."

Just talking, Professor Li Yong's smile faded, and he said solemnly: "There are 50 people in the class, but none of the classmates can do it. I don't want to encounter this situation next time!"

Although the mathematics major in Ludao University is not a strong major, the entire class of 50 people is not as good as one observer. I really don't know whether I should be grateful for my own eyesight or disappointed with my classmates.

The students below all buried their heads. As for Lu Zhou, who was sitting in the first row, he didn't care about this.

"Why does this question do this? Let's look at the first step..."

Professor Li Yong's voice continued to reverberate in the classroom, and after about ten minutes, the get out of class bell rang.

Several of the students in the audience breathed a sigh of relief and smiled, as if this was a life-saving bell.

"This is the end of today's class. Later, I will ask the study committee to send this week's homework to the group, and I will collect it before the next class."

Li Yong paused and reminded kindly, "The homework is all included in the usual grades. I hope there will be fewer students who fail this semester."

The voice fell, and the student's resistance sounded immediately below.

"No! You have homework again?"

"Teacher, it's really going to die!"

"Day 1025 of giving up math!"

"If God can give me a chance to do it again, I will definitely not check the obedience adjustment!!!"

When you were in high school, the teachers always whispered in the ear that it would be easier for you to go to college. However, the reality is that it is still hard work after going to college!

"The feedback from my classmates is very enthusiastic. It seems that everyone likes the homework I have assigned. Then I can consider adding more topics next time." Li Yong smiled brightly. Said, "I'll come to the office with me later."

"OK."

Lu Zhou didn't ask much, and left the classroom with Professor Li Yong.

After the two left, the classroom behind them set off another round of discussion.

"Who is this classmate who came to audit, do you know?"

"I don't know, but this classmate's courage is commendable. He actually came to sit in on Old Li Tou's class!"

"I think there is a great **** coming, and it feels very powerful. I don't know which college it is from."

"Big hairball, I think it's just here to pretend! Who's going to listen to math?"

"+1, I feel like I'm pretending to be a perpetrator. In fact, I can do this question, but I don't think it's necessary to answer it on stage. It's not good to touch too many chalk fingers."

There were also several in the class who participated in this year's Mathematical Modeling Contest, and soon a girl exclaimed:

"I know who he is! He seems to be called Lu Zhou, the champion of this year's Mathematical Modeling Contest!"

As soon as these words came out, the classroom was a little quiet.

...

Office of the Dean of Mathematics Department of Ludao University.

Professor Li Yong leaned back and said to Lu Zhou with a smile, "Student Lu Zhou, just sit down, don't be too polite."

"How did you listen to today's class? Is there anything you understand?" Li Yong asked with concern.

"I understand. Thank you Professor Li for your concern. I really caused you trouble." Lu Zhou sincerely thanked him.

Lu Zhou still respects Professor Li Yong. He helped him apply for a student ID card and a library entry and exit certificate. Not only can he come to audit the mathematics department's courses, but he can also borrow books from the library.

"It's not worth mentioning." Li Yong smiled, and then asked Lu Zhou with great interest, "From the mathematical model at the beginning, it can be seen that you are quite talented in mathematics, and you should learn it by yourself. Less courses, right? What have you learned?"

Lu Zhou didn't even think about it and answered directly: "Mathematical analysis, advanced algebra, analytic geometry, ordinary differential equations, probability theory and mathematical statistics, statistics, abstract algebra, complex variable functions..."

Lu Zhou reported the names of these courses one by one, just like reporting the names of the dishes.

Li Yong, who nodded at first, became more shocked the more he heard the back, and finally waited for Lu Zhou to stop, Li Yong's eyes stared like cowbells, "Are these things you taught yourself?"

good guy! This almost covers all undergraduate courses in digital majors!

"Yes, I have basically finished it, but I haven't fully understood some parts." Lu Zhou didn't understand why Professor Li Yong asked a nonsense, but he answered truthfully.

"Comrade Lu Zhou, you really surprised me." Professor Li Yong shook his head and sighed, as if it was the first time he knew Lu Zhou, and looked at it from top to bottom.

Then Professor Li Yong asked a few questions, and Lu Zhou answered them fluently. Now he also believes that what the other party said is true!

The study of mathematics is like a tree of science and technology with distinct layers. One cannot understand one layer, and the next one can read celestial books. This is impossible to pretend.

Professor Li Yong then asked: "Where is the progress of self-study now?"

"I just started to learn about differential manifolds Differential manifolds..." Li Yong read aloud, then smiled and suggested, "I will recommend you a few books, "Riemann Geometry" by Do.Carmo, Boothby's Differential Manifolds and Riemannian Geometry, and A. Zee's Einstein Gravityina Nutshell, all three are good books."

"I wrote it down, thank you Professor Li!" Lu Zhou's eyes were a little bit eager, and he just looked for the resources of these three books on the Internet as soon as he went back.

Perhaps seeing Lu Zhou's plan, Li Yong shook his head and said, "Comrade Lu Zhou, I want to remind you that knowledge is the most direct way to learn from books."

With that said, Li Yong got up, took down three books from the bookshelf beside him, and handed them to Lu Zhou.

"Fortunately, I still have these three books here. Take them back and read them slowly. If there is something you don't understand, you can come to my office and ask me."

Lu Zhou pursed his lips. Professor Li Yong was as enthusiastic as Principal Chen Hao, and he kept these sentiments in his heart.

"Your talent is very good, but the path of mathematics research is not easy to take. You must guard against arrogance and rashness, and concentrate on your research!" Professor Li Yong taught earnestly.

As if thinking of something, Li Yong reminded: "Well, there is also the paper, you don't touch it now, and I will assign you tasks after you have laid a solid foundation."

Mathematical papers are not easy to write, but Li Yong is very optimistic about Lu Zhou. After a year and a half, he will almost be able to start writing papers.

"A thesis? This..." Lu Zhou touched his nose and said a little embarrassedly, "Professor Li, when it comes to the thesis, I was just about to ask you some advice."

Li Yong's eyelids jumped, suppressing the shock in his heart, and couldn't help but ask, "Thesis? You don't have papers on hand, do you?"

ps: Ask for a recommendation ticket, ask for a monthly ticket!