City: Me, IQ 300

Chapter 22 casually seven middle gameplay (ask for support, sixth change).

Let A=a+b, B=b+c, C=c+d, D=d+e, E=e+a

Then S=ABCDE, A, B, C, D, E≥-2 (each uppercase letter takes an equal sign if and only if the corresponding value two lowercase letters equal -1).

A+B+C+D+E=10.

When S takes the maximum, there are even negative numbers in capital letters dao

1. Four negative numbers, you may wish to set A, B, C, D

……

There are many problem-solving steps listed, but in the eyes of the teacher, it is astronomy.

Because, Ma Aiguo spent a day answering.

This is a real question of the Olympiad, and it is not announced to the public.

“You wrote it? Have you seen it? ”

“No, I just think it’s very simple, in fact, you can solve it with Cauchy’s inequality, it will be even simpler, the core of the problem is…”

Tao Yaoyao quickly covered Chen Fan’s mouth, Chen Fan was a little curious, Tao Yaoyao said: “Wait until they finish you talk, the problem is not easy to get, you prompt, it will not help them.” ”

“Even, okay, but this question is really not difficult, the difficult thing is that the thinking is not comprehensive.”

Still gave a hint.

Chen Fan went to write the rest of his algorithm.

The rest of the students were still struggling to untie up, fretting about it.

By the time the papers could be handed in for the week, thirty minutes had passed.

After the teacher finished reading it, he said helplessly: “After all, it’s a little worse, think again, you don’t have coke.” ”

Oops, nasty.

The girl sat down in her seat with a gag breath and continued to calculate.

The rest of the students also handed in the papers, and all of them committed the same problems as Zhou Ke.

“Are you all trash? Ah, how did you get these first titles? Why did they all make the same mistake for me? ”

Ma Aiguo was really annoyed.

In the past few days, I have been listening to Hua Xiong blowing Chen Fan, he was originally very annoyed, and finally agreed to come down as a training teacher, but as soon as he came, he met such a dismount.

How to teach such students? What to teach”?

However, at Peking University, there is a saying that if you say how many professors are good at mathematics, then there are countless of them.

But you said that the teacher with the best foundation, there is only one, that is, Ma Aiguo.

He may not be the most powerful teacher, not the best at doing problems, but he is the man named after the sweeping monk of Harbin Institute of Technology.

Without a wife, he has devoted his life to the education industry.

No textbooks are required for classes.

Likes to lick plates when eating.

It took a lot of wine for this teacher to open the small stove.

This teacher does not like to open small stoves, he believes that students should be treated equally, and it is best to give other students opportunities.

“All of you, I doubt how you got full marks in mathematics, the papers issued by the education department recently are really getting worse and worse, and you can’t see the level of students at all, Chen Fan, you say.”

Lie in the groove, answer the question”

Can Chen Fan?

Chen Fan got up and said: “The biggest contradiction point is one, four negative numbers that the situation is missing, A, B, C, D take -2, E take 18

.”

S=2^4×18=288 is the maximum value that may exist in this case

But in this case a, b, c, d, e = -1 is not four negative numbers, so in this case S must be less than 288.”

After speaking, Chen Fan returned to the chair from the new one.

Looking at the blackboard, in a daze, I don’t know what I was thinking.

“Do you understand? This question is difficult, but in the Olympiad, this question is given for nothing, you one by one, give me the wrong calculation, if you are still like this, there is no need to participate in the competition. ”

What does the math training teach?

In fact, I don’t teach anything, just do the questions, change the questions, and then expand and extend the knowledge points.

“Your Coke.”

Chen Fan held it in his hand, rarely happy.

Taoyao saw Chen Fan with a smile on her face, and she was also very happy in her heart.

Tao Yaoyao watched crosstalk, heard a sentence, don’t go through the suffering of others, don’t persuade others to be kind, Chen Fan’s childhood experience, which others can’t experience. ，

If Chen Fan really took revenge on the world, then it would be understandable.

“Tomorrow, cheer me up and follow me for a run in the morning.”

Oh my God, this is going to kill.

But I could only accept it with my head down.

A few students left, and Chen Fan took the initiative to find Ma Aiguo.

“Teacher.”

“I’m not your teacher, go aside, Ma Guowei I know, that guy has a very good foundation, you learn well with him.”

“I want to ask the demon group.”

“What? Ma Guowei didn’t advise you? ”

“Persuaded, but I don’t want to give up.”

Alas.

Ma Aiguo said: “If I have a topic in the past few days, you will have it, I will give you everything I will, but the knowledge is a bit much, I am good at theoretical mathematics, that is, you can find all theories in any era and at any stage, I know them all.” ”

“Okay, thanks.”

Bidding farewell to Ma Aiguo, Chen Fan left the classroom.

Ma Aiguo called Hua Xiong.

“Demon group, how to deal with it.”

“If you study it for half your life, give it to him.”

“I’m afraid he’ll fall into it.”

“I’m still worried you’re hiding.”

“What is hidden, some broken theories, it’s useless, you don’t care, then I’ll teach, just this little time, anyway, Mason prime he is good at, the magic group is estimated to be okay, you mathematicians, won’t you teach Chen Fan how to write two words?”

“Have you given up after all these years?”

The phone hung up to Ma Aiguo, but I didn’t expect that when I was old, I sent such a baby student, hoping that Ma Guowei’s foundation was good.

My course, however, was not that easy.

On the staff dormitory side, one student has one room.

In the evening, the rest of the students found Chen Fan.

Everyone shared with Chen Fan the food they brought at home.

Zhou Ke even shared potato chips.

Chen Fan took out the hazelnuts in the village and distributed them to them.

This was prepared in advance by Tao Yaoyao, and Chen Fan could use it when he said this.

Chen Fan looked at the Peking University campus outside the window, now, he is also a Peking University student?

It should be regarded as a Nanny of Peking University, it feels strange.

This little boy, I didn’t expect it, to be so good.

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