After a thousand years of trading, start a million barrels of oil

Chapter 54 Can You Wipe It? (Seek to follow up)

Jiang Fan's words were beyond the professor's expectation, and the other party actually wanted to go to the blackboard to answer the questions.

Not only the professor, but also the students who were watching the excitement below also started whispering.

"He really will? This doesn't feel like a problem that our grade can solve."

"Indeed, I can't even understand the title."

"Didn't you read the question that the professor found from the graduate courseware just now? It wasn't for us at all." The sharp-eyed student noticed it just now.

Someone thought of something and turned to ask a student wearing glasses: "Liu Meng, can you answer this question?"

Liu Meng ranked first in his major in high mathematics last semester, and he was considered one of the top students in mathematics in his major.

In the end, Liu Meng also shook his head: "No, this question is beyond the outline."

Liu Meng has read next year's mathematics textbooks in advance, including when he encounters some derivative concepts in his usual practice questions, he will also look up and understand them by the way.

However, he has barely heard more than half of the core concepts in this question, which is obviously not what they should know in this grade.

"Let's see if he can do it." After a group of people chattered and came to no conclusion, they basically adopted the attitude of waiting and watching the result.

Lin Wan kept her mouth open in astonishment from the moment Jiang Fan said he was going to the blackboard to answer.

This, Brother Fan really knows?
After the professor nodded in agreement with Jiang Fan's request, Jiang Fan went out to the aisle,

Step down the stairs and up to the podium.

First, I nodded and smiled at the professor. After all, no matter whether it was intentional or not, it was true that I disturbed the order of the classroom a little before, and it is normal for people to have opinions.

Then he picked up the chalk from the table, pulled down a blank blackboard,

The blackboard in this classroom is divided into 4 pieces, divided into left and right sides, each side has a piece up and down,
It can be pulled up and down, and the two pieces on the side of the professor have already written words.
The top piece on Jiang Fan's side covers the projector, so Jiang Fan uses the remaining piece in the lower right corner.

Jiang Fan first gave an oral overview of his problem-solving ideas:
"Firstly, the periodic system is expressed as a trigonometric series by using the Fourier series expansion method, and the expression corresponding to the state transition matrix of the Hamiltonian system is obtained by using the fine integration method within one integration step.

Then, through the method of Riccati transformation, the recurrence scheme of the solution of the time-varying periodic coefficient Riccati differential equation containing the state transition matrix is ​​obtained
This method is to make full use of the periodic characteristics of the equation itself. I will use two numerical examples later to show that this algorithm has high computational efficiency and the results are reliable. "

After Jiang Fan finished speaking, he began to write on the blackboard. The whole classroom was silent, and everyone was watching his performance.

After hearing Jiang Fan's discussion, the professor's eyelids twitched,

Just from Jiang Fan's discussion, he already knew that Jiang Fan really understood this question, and the idea of ​​answering it was completely correct.

This really surprised him, this is a freshman class, which means that the young man in front of him is just a freshman,

At this stage, he has the knowledge reserve and problem-solving level that graduate students and even doctoral students in the mathematics department should have. Did he discover a genius?

But no matter what, let’s look at his specific argumentation process later,

The right idea can already give him 90 points, but will he present himself with a beautiful 100 points?

The professor is looking forward to it.

Jiang Fan wrote vigorously on the blackboard. Lines of expositions and formulas were displayed with the sliding of the chalk.

The professor is in class time, and these freshmen should not be able to understand this topic,
So I arranged for them two after-school exercises on Fourier series, so that they can use Jiang Fan's writing on the blackboard to do it, and I will explain it to them later.
But except for a few people who flipped through the textbooks for a few tokens, everyone else was still staring at Jiang Fan's writing intently,
Although they couldn't understand what Jiang Fan wrote, they just thought it was awesome and wanted to read it.

Seeing this situation, the professor ignored it and focused on Jiang Fan's writing on the blackboard.

Jiang Fan quickly filled the blackboard. No matter how the upper part of the blackboard was pulled down,
Because there is a projector blocking it, it will always cover part of the content.

Jiang Fan looked at the professor, who understood what he meant, and motioned to the blackboard on his side:
"It's okay, just wipe off my piece."

With permission, Jiang Fan went to the professor's side of the blackboard, erased part and wrote part,

Fortunately, there is no need to erase all the two blackboards on this half, and only one blackboard has 3/4 written on it. Finally, the entire argumentation process has been written.
Of course, in order to save everyone's time, he simply wrote down some expository content, focusing on clearly writing the core argumentation process and formulas.

Jiang Fan was busy for a long time, and then simply scanned again to confirm that there should be no major problems.
Putting down the chalk in his hand, he smiled and said to the professor, "It's finished."

"Wow~" The whole classroom was amazed,
Although they can't understand it, it doesn't stop them from being amazed.

The professor nodded at the side. He had already read Jiang Fan's entire exposition in the process of writing it.
Very good, with rigorous logic and clear organization. There are even two details that are a little simpler than the standard answer, and there are basically no faults.

"Very good, go back to your seat." The professor smiled rarely, and said to Jiang Fan,
At the same time, he pointed to the blackboard and said briefly to the students: "That's right."

"Wow~" the students exclaimed again, this time louder than before,
After all, they just thought that Jiang Fan's whole set of movements was very cool, but they couldn't understand what the result was.

But this time, the professor personally verified that this boy not only solved the problem with a very handsome set of actions, but also the result was correct.

This is amazing, so this time it is really a surprise from the bottom of my heart.

"Okay." Jiang Fan also smiled and nodded to the professor, then walked along the steps in the middle towards the row where he was sitting.
Along the way, the students on both sides cast their gazes, amazed and envious, wondering which great god this is.

Jiang Fan came to his row of seats and walked in along the gap left by the students' legs.

Seeing Lin Wan, Lin Wan's gaze at this moment is of course looking at herself with a smile, her eyes are shining,
But he noticed one thing in particular, that is, Lin Wan's body is sitting very straight now,

Originally, he watched Lin Wan in class today, even before the two of them spoke, Lin Wan's upper body was half bent during class,
It seems that I am afraid that others, especially the teacher, will notice me.
This is the unconscious performance of many scumbags. They are most afraid of being noticed, so they hope that they will be buried in the vast crowd and not be found, especially asking questions.

Of course, this is a thin-skinned scumbag like Lin Wan,
If it's Jiang Fan, who won't do it after being called out,

He will also show a sunny and charming smile, and then answer loudly in decibels that even the students in the corner of the classroom can hear clearly:
"Teacher, I won't!"

But Lin Wan wasn't so thick-skinned, so she subconsciously made this gesture to try to hide herself.

But at this moment, her waist was straight,

It seems that I hope that the eyes of the whole world will turn to me, and let everyone know,
The boy who dominated the podium just now and solved a super difficult problem came with him.

Jiang Fan also showed a sunny smile towards Lin Wan. He was very happy to be Lin Wan's pride, because Lin Wan was also his pride.

For the remaining half of the class, the two were very honest and did not dare to chat anymore.
But from time to time, there will be eyes cast on them.

The bell rang for the end of get out of class, Jiang Fan and Lin Wan accompanied the crowd to leave the classroom, walked to the door,

But suddenly someone stopped them: "That classmate, please stay for a while."

Jiang Fan turned his head and found that it was the professor who stopped him.

　Chapter 3 today, please follow up

　　
　
(End of this chapter)