Xueba, I beg you to go and escort him quickly!

Zhu Tiesen laughed, "I've always wanted to see how Xu Heng lectures!"

"You may not know that the physics teacher in their class was sick, and he took over as a substitute for a month. As a result, their physics scores from the bottom of the class took the first place in the school grade!"

Everyone, "!!!"

"In addition, he also taught all the courses that the teacher will teach in the next two months!"

Everyone, "!!!"

"The physics teacher almost went on strike! Just in time for the class division, the students in the class he taught were divided into different classes. As a result, the teacher gave a lecture. They knew everything, and they stood up and refuted, causing the physics group of the whole grade to complain again and again! "

This matter was asked by Zhu Tiesen when he personally contacted the principal of Yunshan High School to learn about Xu Heng.

Everyone opened their mouths wide, and they didn't even know how to be shocked!

"Sure enough, I am a frog in a well! My God! He is too strong!"

"What grade is the first, what is recommended, I feel that they are all scumbags..."

"Is the standard for judging academic masters so high now?"

"Xueba, you must be able to lead the whole class to take the first place! You must be able to become the winner of the Mathematical Olympiad competition?!"

"..."

The students no longer knew how to describe what they heard.

Xu Heng stood on the podium and looked at the 100 people in the audience calmly!

nervous?

Excited?

None exist!

It's not that Xu Heng has never attended class!

This time, it was just a little more people.

"Hey……!"

Sighing, Xu Heng cleared his throat and spoke.

Because this is a big classroom, and Xu Heng's voice is loud.

Just a few words attracted the attention of passing Tsinghua students.

"This voice is so young...Which teacher is it?"

They are attracted by the sound at first, but they can take a closer look through the window.

very young!

Obviously a student...

This student is so brave!

How could he be teaching so many students in the audience without any hesitation? !

……

PS: Thank you [Ye Jiuzhi] [Rain hits plantains and wind brings sorrow] [Tail number 2084] [In the name of zero] [FOX, LOVE?] [dayiwzj] [...] [Tail number 8062] [Long long past A series of scars] [brown sugar chocolate] [qwdn] [kuangsan saigao] [no such name] [tail number 1627]!

Thank you for your company and support!

There are still no thanks, the author knows that you have been supporting silently.

You are the motivation for the little author to keep breaking out!

Since it was put on the shelves, it has more than 2 words per day, and the little author has been gritting his teeth and persisting... Whenever I want to give up and do less, I will look at your support and let myself persevere!

thank you!

With you all the way!very nice! ! ! .

Chapter 198

"Let P be a polynomial of degree n satisfying conditions (1)(2)(3)."

"Because it is impossible for a constant polynomial to satisfy (2) and (3) at the same time, n≥1."

"In (2) let a=b, c=-2a, then get 0=P(2a,-2a)+P(-a, a)+P(-a, a)= from the homogeneity of P [(-2)n+2]P(-a, a) If n>1, then P(-a, a)=0, so P(x, y) can be divisible by x+y."

"Assuming P(x, y)=(x+y)P1(x, y), then from (2) we get P1(a+b,c)(a+b+c)+P1(b+c,a )(a+b+c)+P1(c+a,b)(a+b+c)=0, so P1(a+b,c)+P1(b+c,a)+P1(c+a , b)=0."

“P1仍是齐次的，且P1(1，0)=P1(1，0)(1+0)=P(1，0)=1。”

“即P1也满足条件(1)（2）(3)，它的次数为n-1．如果n-1＞1。”

"It is also possible to construct a homogeneous polynomial P2 of degree n-2, which satisfies the conditions (1) (2) (3), and p1(x, y)=(x+y)p2(x, y)."

"If you go on like this, you will always get a first-degree polynomial Pn-1(x, y)=mx+ny."

The problem Xu Heng is currently facing is this question!

He directly said a different way of solving the problem.

On the blackboard, he writes and draws, giving key points.

The students raised their ears and listened carefully.

Xu Heng enunciated clearly and his voice was rich.

Standing on the podium, since he spoke the first sentence, he became more and more confident after that.

"So, do you understand this question?"

With so many students, everyone's understanding ability is different.

And Xu Heng explained it too fast!

A classmate stood up, "I'm sorry...can I do it again? You, you spoke too fast...our thinking didn't keep up!"

Xu Heng, "Er... 18..."

Several other students raised their hands in agreement.

"Yes! Student Xu Heng! Slow down, can you?"

Xu Heng frowned slightly, then turned to look at the blackboard.

Still don't understand? !

A headache!

Xu Heng turned around and looked at Zhu Tiesen for help.

Zhu Tiesen immediately stood up and shook his head, "I don't need to explain! It's because you spoke too fast! It's not that they don't understand!"

Zhu Tiesen immediately pointed out the problem!

He's not stupid either!

He has to analyze and explain it again, isn't it killing him?

He doubted whether he had the ability to prove it!

One plus one equals two, simple!

But it is difficult to prove that one plus one equals two!

The moment Zhu Tiesen stood up, the surrounding students realized that there was still a teacher in this classroom!

Zhu Tiesen, "Student Xu Heng, tell me again!"

classmate!

Sure enough, Xu Heng, who was so young on the podium, was a classmate!

Many Tsinghua students who had doubts had answers in their hearts.

On the podium, Xu Heng was a little embarrassed.

"Yes... I'm going to say it again, I'm going to say it a second time... I should have said it a little slower... it's just..."

Students, "???"

Zhu Tiesen, "???"

Xu Heng scratched the back of his head, twitched for the first time, and said, "It's just that I'm afraid I said something different..."

Are you... different?

What's the difference? !

???

The students looked at each other in blank dismay, unable to react for a while.

"What do you mean? Xu Heng, what do you mean?"

"Wait! I seem to understand?"

"Student Xu Heng, you, you, you...don't tell us, the method you just mentioned was just improvised! As soon as you say it, forget it!"

"Then how many ways do you have to solve the problem?!"

Rumbling--

These words, like a depth bomb, detonated the audience!

Everyone stared at Xu Heng on the podium.

He was very embarrassed and acted a little embarrassed.

"He didn't answer, did he just acquiesce!"

Everyone almost turned the table over!

"Student Xu Heng, how many ways do you have to solve the problem?"

Xu Heng, "Uh... There are several, several... But the most important thing right now is not this, the important thing is..."

Pfft! ! !

If everyone can vomit blood, a mouthful of old blood might be able to vomit three meters high!

"Is there anything more important than this?"

"If I were the go-getter in the king, I would definitely throw my wife on you! It's so annoying!"

"Count me in! If I were Daji...uh...Daji is sending love, if I were Houyi, I'll open the door, whoosh you!"

"Student Xu Heng, be yourself!"

"..."

Some of the onlookers from Tsinghua University were also shown off by Xu Heng's operation. They couldn't help but took out their mobile phones, took short videos and sent them to their class groups.

"There is a student in the Olympiad class who is giving a lecture! Come and watch!"

"This classmate is too handsome!"

"Is it possible? I don't seem to know how to answer the question on the blackboard? Should I ask my classmates from the mathematics department to take a look?"

"Are all the students now so powerful?"

"..."

In and out of the classroom, there are discussions.

Xu Heng stood on the podium and looked at everyone, "The important thing is, tell me, what kind of problem-solving ideas I just talked about?"

Because there are several similar ideas, if Xu Heng says something wrong, it will confuse the students.

At this time Dong Fangyuan stood up, "Student Xu Heng, you used the unsatisfactory condition, homogeneity..."

Xu Heng immediately regained his composure, "Okay! I got it! Thank you!"

With Dong Fangyuan's assist, Xu Heng explained the question again.

This time, he changed to a different way of explaining, very slowly.

His typhoon is stable!