A genius? I just love studying.

Chapter 72 Dharma Protector
The others were not as calm as Lin Xiaotang and the others.

Dadi Internet Cafe is right next to Rongcheng No. 2 Middle School. 50% of the people inside at this moment are students from Rongcheng No. 2 Middle School who sneaked out to surf the Internet. When they saw the principal and vice principal coming over with security guards in a menacing manner, they all became silent like insects hearing thunder.

They jumped up from their seats and fled in all directions.

Suddenly the entire Internet cafe was in chaos.

However, Wu Huachun and his companions ignored the fleeing students and walked straight to where Chen Hui was.

"Old An, what are you doing here?"

"Why don't you take him away quickly? Do you still want to wait for him to finish this fight?"

Zhao Defeng easily found An Chengzhang standing behind Chen Hui. He immediately became furious and started yelling at him.

"Shh!"

An Chengzhang also turned around angrily and gestured to silence several people.

At this time, Zhao Defeng and others also came to the back of Chen Hui's seat. When they saw the content on the computer screen, they naturally shut up.

How could they not understand that they had misunderstood Chen Hui? Chen Hui did not come to the Internet cafe to play games at all, he came to take an exam!
Chen Hui could probably feel something of what was happening behind him, but now he had no time to pay attention to what was happening behind him.

The fourth question really started to get more difficult.

This question still tests your knowledge of linear algebra and advanced algebra. In essence, it defines a linear transformation. This linear transformation is relatively sparse, with non-zero values ​​only on the secondary diagonals above and below the main diagonal.

The test-taker is required to analyze the eigenvalues ​​of this linear transformation, the sum of the eigensubspaces, etc.

This problem is not difficult to solve. The idea is very natural. You just need to operate and analyze the matrix.

First, we just need to prove that all the eigenvalues ​​of f are -d, -d+1,..., d, then find the matrix representation of the linear transformation f in a given basis, and finally calculate the characteristic polynomial and solve the eigenvalue.

However, according to the definition of the characteristic polynomial det(F-λI)=0, where I is the identity matrix of (2d+1)(2d+1), calculating this determinant is a very complicated process, which requires the use of various properties of the determinant, such as row-column expansion and recursive relations.

After a series of calculations and simplifications, we obtain a (2d+1)th-order polynomial equation about λ. Solve this equation and prove that its roots are -d, -d+1, …, d.

call!
Chen Hui let out a long breath.

This was just the first question, but it took him a full half hour.

The question itself is not difficult, but to get the correct answer in such complex calculations and transformations, very solid basic skills are also required.

This was only the first question, there were two more to come. Chen Hui took a quick look at the question and realized that not only would he need to calculate characteristic polynomials and solve higher-order equations, but he would also need to analyze the dimensions of the solution space of various linear equations.

These are extremely complex and tedious processes.

I'm afraid it will take several hours to get it done!
After a brief analysis, Chen Hui immersed himself in calculations again, waving his pen rapidly on the draft paper.

After all, he had only been using computers for a short time, and he was not yet used to solving problems on the computer. He wrote down the solution process on a piece of draft paper and then copied it into the computer.

He didn't know that his action had already made An Chengzhang, who was standing behind him, open his mouth wide.

An Chengzhang suddenly felt uncertain whether the little guy had skipped the third question or had already finished it.

If it's the latter, that's too outrageous!
Half an hour, and finished three questions?

But now Chen Hui has already answered the first question of the fourth question. Although he doesn't know the answer, this is a proof question. Chen Hui's thinking is correct, and this question is likely to be correct.

The key point is that he doesn't know the answer to this question either.

Although he was a graduate student in mathematics, he had devoted himself to high school education for so many years that he had forgotten many things. It was only after seeing Chen Hui's answer that he recalled these things and completed the verification according to the answer.

In other words, Chen Hui's math level is now far superior to his!

Just how good is this little guy's math ability?
An Chengzhang was secretly shocked. It’s only been a few months?
He watched this little guy grow up step by step to where he is now!

Monster! This can no longer be explained by the accumulation of experience. The content Chen Hui used to solve the problem is already accessible only to graduate students in the Department of Mathematics. Only a monster can achieve this level in such a short time!

Zhao Defeng had long forgotten mathematics, and Wu Huachun didn't understand mathematics, but they were both smart people and knew how to judge people.

An Chengzhang's reaction had already told them all the answers.

The two looked at each other and saw surprise in each other's eyes.

They did not agree with Chen Hui's participation in the Barbaria Mathematical Competition, and they also knew the difficulty of this competition.

But now it seems that the situation is a little different from what they imagined.

"Old An, come out with us."

Zhao Defeng patted An Chengzhang's shoulder and spoke softly, holding his breath, for fear of disturbing Chen Hui who was doing the test.

Then he instructed Zhao Dayong and the other two security guards, "Just keep an eye on Chen Hui here. Don't let anyone disturb him."

Only then did he turn around and walk out of the internet cafe. Standing at the door, Zhao Defeng breathed a sigh of relief and finally dared to speak loudly, "Lao An, what's going on?"

"The Barbaria Mathematics Competition preliminaries begin today."

An Chengzhang replied unhappily, isn't this obvious?

"I mean, why did you let him do his homework in an internet cafe?"

Zhao Defeng rolled his eyes. He had been in officialdom for a long time and was quite sophisticated, but sometimes he would still be annoyed by some straightforward teachers.

"I was negligent."

An Chengzhang did not put all the blame on Zhang Anguo. His original intention was to let Chen Hui give up, so he did pay less attention to Chen Hui these days.

"No matter what, let him go back to school and take the exam first!"

Wu Huachun said, "I'll have Xiao Feng prepare an office and set up the internet. Then I'll take Chen Hui back to school."

"Old Wu is right!"

Zhao Defeng immediately agreed with both hands. Although they were not optimistic about Chen Hui's participation in this competition, they could not do such a thing as to let Chen Hui take the exam in an Internet cafe and mistreat their school's treasure.

Wu Huachun didn't waste any time and took out his cell phone and started making a call.

"By the way, what is Chen Hui's current level?"

Taking advantage of this opportunity, Zhao Defeng asked curiously, "You know, I haven't worked on the front line for many years."

An Chengzhang recalled the scene just now and organized his words before saying, "The Barbaria Mathematics Competition preliminaries have seven questions, ranging from easy to difficult, with a full score of 120 points. Based on past experience, around 45 points will qualify for the finals. Chen Hui just solved the first question of the fourth question. If he has no problems with the previous questions, he will already have a score of around 45!"

"what?!"

Zhao Defeng opened his mouth wide.

Although he was not very good at math, he had heard of the Barbaria Mathematical Competition and knew that many teachers from top high schools would participate, but many of them could not even make it to the finals.

Nowadays, middle school teachers are at least graduate students, and most of those who want to participate in this competition graduated from mathematics departments.

"The time limit for the preliminaries is 48 hours, and only a little over an hour has passed!"

An Chengzhang, who never stops making shocking remarks, added.

Wu Huachun, who had just hung up the phone, narrowed his eyes and called the number again, saying hurriedly, "As you said just now, can you prepare it in half an hour?"

(End of this chapter)