Omnipotent Data

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Cheng Nuo Xueba Lecture Hall has started!

What should I do if I can't do the scum problem?

It's probably a fee!

Just a bottle of Shenbao!

Cheng Nuo picked up two bottles of Kidney Treasures from the bookshelf, handed them to Zhao Yang and Li Peng each, and then started his Xueba lecture hall mode. The fastest update┏Ⅹ④③⑨⑨┛

Cheng Nuo has already read the three questions that Zhao Yang can't do.

Judging from the countless number of women in Cheng Nuo's reading...Ah, from the experience of reading countless questions, these three questions are more difficult than general postgraduate entrance examination questions.

No wonder Zhao Yang, who Cheng Nuo thinks he has a good level of mathematics, only made two of the five questions.

"Do you really know how to do it?" Zhao Yang cast a suspicious look up and down.

Zhao Yang has a very deep understanding of Cheng Nuo's talent in mathematics after more than a month of understanding.

It can be said that it is definitely not accidental that Cheng Nuo became the only full score in mathematics in the college entrance examination.

So, when he encountered a problem that he didn't know, the first person Zhao Yang thought of was Cheng Nuo.

can……

High talent goes to high talent.

Zhao Yang still couldn't believe it. The problem he couldn't solve after several hours was in Cheng Nuo's hands, and he had calculated the correct answer in less than two minutes.

Facing Zhao Yang's doubts, Cheng Nuo shrugged indifferently, "Will I do it? Wouldn't it be clear after listening to me?"

With a half-believing mentality, Zhao Yang and Li Peng looked at each other and sat back next to Cheng Nuo again.

Cheng Nuo smiled, took out a pen, brushed it a few times, and wrote the title on the draft paper first.

Cheng Nuo first talked about the third of the five exercises.

"Find ∫dx/x^4+1 and ∫dx/x^4+x^2+1."

In terms of difficulty, this is the easiest of the three questions.

Compared with ordinary indefinite integrals, the difficulty is naturally not at the same level.

The methods of exchanging elements, simplifying, making up points, and integrating parts by parts cannot solve this problem.

"I used four or five integration methods for this problem, and it seems that none of them can be solved smoothly." Zhao Yang frowned and said, "I guess it should be an alternative solution method, but what should I do? I haven’t figured out how to write the formula."

Cheng Nuo turned his pen, nodded and smiled, "You are right. This question really cannot be solved by the four conventional solutions taught in class. It's hard to say whether the correct answer can be calculated in the end. "

"Then what calculation method should be used to solve this problem?" Li Peng, who had been silent, asked curiously.

Cheng Nuo spoke slowly, "Hua Luogeng's integration method."

"Hua Luogeng's integral method?" Obviously, both of them felt very strange to this term.

"Hua Luogeng's integral method is a combination integral method proposed by Mr. Hua Luogeng for solving integrals." Cheng Nuo explained, "Actually, it doesn't matter whether you know this integral method or not, as long as you can use it. Look..."

Cheng Nuo wrote the specific calculation steps of this problem on the draft paper.

∫dx/x^4+1+∫x^2dx/x^4+1=∫(x^2+1)dx/x^4+1=∫d(xx^-1)/(x-…… ...

∫x^2dx/x^4+1-∫dx/x^4+1=∫…………

Subtract the two formulas to get the value of ∫dx/x^4+1.

In Cheng Nuo's writing, the calculation steps that Zhao Yang thought were extremely complicated were just three simple formulas.

"Hey, this is the calculation process of Hua Luogeng's integration. With this integration method, the problem becomes very simple." Cheng Nuo said very relaxedly.

"The rest is for the ∫dx/x^4+x^2+1, the truth is the same, you can get the same directly." Cheng Nuo didn't bother to calculate the second integral method.

The calculation method has been told to Zhao Yang. If Zhao Yang can't count it, then just drop out of the group.

Zhao Yang nodded, "Well, I did think this problem was complicated before. But then again, how did you know Cheng Nuo that this is called...Hua Luogeng points?"

This is where Zhao Yang is curious.

The same school, the same teacher, the same course. Even Cheng Nuo skipped a few minutes last week.

But why Cheng Nuo would know this Hua Luogeng points, and he didn't understand anything.

Zhao Yang can’t remember that when the teacher of Shufen was in class, he talked about this problem-solving theorem.

"Oh!" Cheng Nuo picked up the thermos cup on the table, took a sip, patted Zhao Yang on the shoulder, and said earnestly, "Student Zhao Yang, as students of Tsinghua University, we should not just be satisfied with the teacher. The knowledge taught in the classroom."

"The millions of books in the school library are not for you to watch from a distance. Use your extracurricular time to enrich yourself as much as possible!"

"Didn't you ask me how I knew Hua Luogeng's integral?" Cheng Nuo said, took down the book "Differential Mathematics and Its Application" from the shelf and put it in front of Zhao Yang, with a serious tone. "The third chapter of this book The fifth section of this chapter is about the content of Hua Luogeng’s points."

Zhao Yang took the "Differential Mathematics and Its Applications" and turned to the page Cheng Nuo said.

And the title of that page is impressively-"The Nature of Geodesic in Differential Geometry"!

This has half a dime relationship with the special Hua Luogeng points!

"Cough cough..." Cheng Nuo coughed a few times, then smiled, "I have a wrong memory, I have a wrong memory. Okay, let's skip this topic and look at the fourth question."

Cheng Nuo originally wanted to use this reason to preach, but now it seems that he has already messed up.

Cheng Nuo took Zhao Yang's workbook and continued on to the fourth question.

"Find the limit of sequence l=lim(arctann+1/n-π/4)√n^2+n."

This topic is not too difficult for Cheng Nuo.

Basically, there is no need to think too much. Swish Swish, under the gaze of Zhao Yang and Li Peng, Cheng Nuo wrote down his own solution steps on the draft paper.

"Π/4=arctan1, arctann+1/n=arctan(1+1/n

"F(x)=arctanx,..."

The calculation formula for this topic is a bit more complicated.

But for Cheng Nuo, it's just a little bit more complicated.

In less than two minutes, Cheng Nuo had already written the final stroke.

"L=lim......=0.5."

Ignoring the surprised eyes of the two next to him, Cheng Nuo directly counted the fifth question.

It is still a question of seeking the limit.

However, the required limit formula is very complicated, and it is impossible to solve the Lagrangian median theorem, the Law of Lagrangian, the theorem of forcing, and the Taylor formula.

Cheng Nuo took another approach, combining Cauchy's convergence theorem with Stolz's theorem.

"Limf(x)/x^n+1=limf(x+h)-f(x)/(x+h)^n+1-x^n+1……"

After a dozen formulas, Cheng Nuo solved the problem easily.

"Do you understand?" Cheng Nuo asked the two of them while closing the cap without looking up.

"There are still a few formulas in the fifth question." Li Peng tells the truth~www.readwn.com~ Come, take it, take it back to the dormitory and take a look. "Tear it, Cheng Nuo tore off the page of the draft paper and stuffed it into Li Peng's hand.

Li Peng and Zhao Yang got up, "Then Cheng Nuo, thank you, Li Peng and I will leave first."

Cheng Nuo waved his hand, "You don't need to thank you, classmates, you should help each other."

Zhao Yang nodded, "Then Cheng Nuo, if you encounter any trouble in the future, we will try our best to help."

Cheng Nuo smiled, "That feeling is good."

After being polite to each other, Cheng Nuo watched Zhao Yang leave the dormitory.

As soon as he closed the door of the dormitory, Cheng Nuo quickly squatted on the computer desk and shouted eagerly at the other three people in the dormitory, "Quickly, while there is still time, I will start another round as soon as possible. I don't believe that this round will be returned. Can't eat chicken!"

…………

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