In the afternoon, the woods.

After Cheng Nuo finished class, he arrived on time.

On a stone table for rest in the woods, Wang Genji had already been waiting here.

Seeing Cheng Nuo coming, Wang Genji waved at him, "Here, here."

Cheng Nuo came to the stone table and sat opposite Wang Genji.

The grove is a rare area on campus. Except for the occasional couples who are reluctant to spend money to stay in hotels, basically few people come here.

The wind blows the leaves and makes a rustling sound.

In the quiet woods, on the stone table, Cheng Nuo and Wang Genji sat opposite each other.

"Let's... let's start." Wang Genji glanced at Cheng Nuo, took off his coat, and spoke slowly.

Cheng Nuo nodded slightly and took a deep breath, "Well, senior, come on!"

Wang Genji took out a stack of a4 paper from his schoolbag beside him.

That was the paper he printed in advance. There were seven pages in total.

He handed Cheng Nuo the printed paper and looked at Cheng Nuo with eager eyes, "Can you tell me now, which step of my paper went wrong?"

He didn't sleep well all night yesterday because he had been thinking about this.

Just this afternoon, he came to this woods just after lunch and waited for Cheng Nuo early.

Even if you die, you must understand.

Wang Genji didn't know if he could save this paper. But at least, he had to know where he made a mistake.

Cheng Nuo smiled and took the paper, shrugged, "Of course."

Cheng Nuo took out a pen from his pocket, turned to the second page of the paper, and drew a heavy horizontal line under a formula. "Bo, this is this step. Senior, how did you push this formula from the previous formulas?"

The formula drawn by Cheng Nuo is one of the first few derivation formulas of the new solution proposed by Wang Genji.

In the paper, Wang Genji wrote that a random differential equation of blak-sholes, for example: d=1(udt+σdb1)

Write out the pseudo-homogeneous differential equation of this random differential equation, d=σdb, so...

Suppose another equation f(x)=(t)e^σb*t, substitute the maximum and minimum values ​​after the first order derivative into the pseudo-homogeneous differential equation of the original equation, and then use Riemann integral to solve it, and finally use the ito formula to find the differential.

The key is the process of substituting the maximum value of the first-order f(x) derivative written by Wang Genji.

"What's wrong? Is there any problem with this step?" Wang Genji looked confused.

He thought Cheng Nuo would say that the mistake he made was in the middle and late part of this paper.

After all, there are too many formula calculation steps in the latter part of the paper and it is too complicated.

Wang Genji could not confirm 100% whether he would make a mistake somewhere.

But Cheng Nuo pointed out the place he saw, but he was at the beginning of the paper.

Seeing that Wang Genji's mind had not turned around, Cheng Nuo frowned slightly and explained patiently, "Senior, you have set a f(x)=(t)e^σb*t here, and then substitute the maximum and minimum values ​​of its first derivative."

"But how can you be sure that the f(x) you set must have a maximum value or minimum value?"

"+∞ and -∞ are both possible!"

"When the maximum value of the first derivative is positive infinite or the minimum value is negative infinite, the following formula is simply impossible to hold."

Cheng Nuo finished his judgment word by word.

Opposite Cheng Nuo, after listening to Cheng Nuo's words, Wang Genji's expression turned pale.

Wrong! It's indeed wrong!

He was really wrong in this place!

When he was writing this, he just mentioned it all. Or, he took it for granted.

There is no consideration to the absence of a maximum and minimum value.

As a result, a small mistake caused the entire paper to collapse.

Now, after more than four months of hard work, it has all gone to nothing.

I'm not willing to accept it! I'm really unwilling to accept it!!

But then what can I do?

If such a big mistake occurred in the thesis, even if it was a major repair, I'm afraid it would not be able to be rescued.

There is no chance!

Wang Genji smiled bitterly, picked up the paper placed on the stone table, tore it apart, and threw it into the air with force.

Broken pieces of paper were sprinkled down one after another.

Wang Genji looked like he was desperate.

Cheng Nuo looked at Wang Genji with a confused look on his face, "Senior, why did you tear the paper?"

Wang Genji was stunned and spoke in an extremely painful tone, "Cheng Nuo, you don't need to comfort me, I've already seen it."

"Isn't it just a SCI paper? It's a little bit, really, a little bit."

"This paper is a waste anyway, and it's boring to be sad. There are opportunities in the future, and I will try my best to write a satisfactory SCI paper."

After saying that, Wang Genji got up, carried his schoolbag and was about to leave.

The back is bleak and desolate.

Cheng Nuo called Wang Genji, "Senior, I didn't seem to say... This paper cannot be modified!"

"What?!" Wang Genji suddenly turned around and looked at Cheng Nuo with a deep shock, "Cheng Nuo, you... what did you say just now?"

Cheng Nuo smiled and repeated the words, "Senior, your paper is actually not as bad as you think. If you change it, it should still be useful."

"Are you telling the truth?"

"Senior, I don't need to lie to you. I also calculated the simple solution to the linear random differential equation in your paper. In theory, this method of first finding the pseudo-homogeneous equation and then verifying the solution of the variable constants is indeed effective. However, in the specific calculation process, it still needs to be carefully considered."

After hearing Cheng Nuo's words, the expression on Wang Genji's face quickly turned from gloomy to sunny.

As long as there is still rescue! As long as there is still rescue!

He continued to sit opposite Cheng Nuo, looked at Cheng Nuo with affectionate eyes, and spoke with a gloomy face, "Cheng Nuo, come on, let's discuss it in depth."

Subconsciously, Wang Genji wanted to take out the printed paper from his schoolbag. Then he tragically realized that the paper had been torn to pieces by himself.

There was no choice but to climb under the stone table and try to put the torn paper back.

It happened that at this moment, a cleaning lady passed by here. She glanced at the direction of the stone table, and then widened her eyes.

From her perspective, at the stone table, two boys, one of them was lying under the stone table, kneeling on their knees, supporting the ground with both hands, and their heads were blocked by the legs of another boy. More importantly, the body of the boy who was lying under the stone table was still moving back and forth. The other boy leaned back slightly, with a very comfortable expression.

That picture, tsk tsk...

"Are young people nowadays so open?"

The cleaning lady lamented that she was really old. Is the current social atmosphere so open?

The cleaning lady kindly reminded the two of them and shouted loudly. "Hey, two young men, don't do any foreplay, hurry up and do it. I saw someone coming to this place."
Chapter completed!