Seeing a student who hadn't studied for a long time pick up a pen, every teacher was pleased.

Pan Shuai said thoughtfully: "Perhaps, we should give those classmates a little attention~"

The other teachers all nodded yes

Soon came to the last big topic, Chen Fan had already returned to the podium, and he spoke in plain words:

"Now I will write the steps of solving the last big problem, you can copy the solution process first, and the class will be over immediately, and leave it for a little research after class!"

Then Chen Fan's neat regular script appeared on the blackboard

By a=1, b=1,

It is learned that f(x)=lnx/x+1+1/x.

So, f(x)-(Inx/x-1+k/x+k/x)=

1/1-x^2(2lnx+（k-1）(x^2-1）/x）

........

Proof: The value range of k is (-00,0]!

Chen Fan writes quickly, but also in detail.

The teacher had a hard time solving this question, after all, it was the last finale

The teacher who watched it was also Chen Fan who was writing according to the answers posted above

But soon they abandoned this idea

Because after Chen Fan copied the question, he wrote a solution method below

A solution 1 is written on the previous method

Written before this answer

Solution 2

lnx/x+1+1/x>Inx/x-1, i.e. Inx/x+1-lnx/x-1>k-1/x,

i.e. k-1<2xlnx/1-x^2

·······

Proof: The value range of k is (-00,0]!

And then

Solution 3:

Let g(x)=2xlnx/1-x^2, then g(x)=(2lnx+2)(1-x^2)+4x^2lnx/(1-x^2)^2,

namely

.....

Proof: The value range of k is (-00,0]!

And then

Solution 4

Solution 5

.....

Solution 8

....

Finally, feeling that class was about to end, Chen Fan pulled out another blackboard.

Remove the new chalk

It's just two

One in one hand, left and right open the bow, both pronged.

Wrote on the blackboard

Solution 9 and Settlement 10

The students and teachers at the bottom have been numb to copy the answers

I don't know what Chen Fan is writing at all

Whatever, just copy it!

Pan Shuai in the back smiled bitterly: "I finally know why Teacher Li is looking for Chen Fan, you must know that several teachers in the mathematics group took half an hour to do this problem!" ”

There were also teachers from the mathematics group who were present, and they also spoke: "But Chen Fan actually used ten methods to adjust this problem!" It seems that we still underestimate Chen Fan. ”

All the teachers nodded yes

I had to take it

The level of many teachers of all kinds is not much higher than that of top students!

Their advantage is that they have more experience and more ways to do problems.

The horizon is much wider than that of students

Chen Fan may be terrifying in their eyes

Because they can only teach students a lot of problem-solving methods

If these methods do not go deep into the roots, they will inevitably be jerky and difficult to understand in the ears of students.

But the horror is that Chen Fan is able to tell the students about every step of thinking!

What is thinking?

In fact, sometimes you do a problem, and you don't know what method you use or what kind of mathematical thinking you use! What kind of logical relationship is used!

Including many teachers are like this

The answer is one word

The students listened

That's it!

Students don't seem to understand, teachers take it for granted!

Because that's how he came back in the first place!

So high school is hard!

It's hard for teachers, let alone students!

Therefore, the college entrance examination is the way to select talents!

The bell rings for the end of class

Chen Fan: "Well, there are many new beginnings in life, every year is a new beginning, every month is a new beginning, every day is a new beginning, for us students, every new workbook, that is a new beginning, so ......"

The students also listened carefully

But the more I heard about the end, the more I realized that the way was wrong!

This Nima is not a noble chicken soup for the soul

It's a poison that destroys itself

"Xueshen, oh no, it's Teacher Chen, don't!"

"It's the same root, why be too anxious to fry each other!"

"That's right, Teacher Chen, you are also a student, don't you have to do it when the workbook is handed out?"

"yes, yes, don't send it! Hello I'm hello, hello everyone, don't send it! ”

The students cried for a while, and let out a ghost cry wolf howl!

Chen Fan was unmoved, and said calmly: "Class leader, go to Teacher Li's desk and count out the stack of exercise books fifty-seven!" ”

"Count you ruthless!"

"Awesome, I actually chose to die and break the net!"

"Die together, count yourself ruthless!"

"Chen Fan wants to do this!"

"What good is it for you to exhaust us?"

However, Chen Fan didn't seem to know the pain, and looked at the students who were complaining frantically with a smile!

Qiao Yingzi, who knows Chen Fan deeply, knows that Chen Fan will not make such a "low-level mistake", and has realized that it is wrong.

"Teacher Chen Fan, why did you ask the class leader to check the fifty-seven workbooks?" Qiao Yingzi already had a guess.

Chen Fan was stunned for a moment, but he didn't expect that someone had already realized that something was wrong!

Yingzi has become smarter recently, and her brain has become more responsive!

Chen Fan thought so, but he didn't hide it, and said loudly: "Because the teacher said that Chen Fan's level is too high, there is no need to make an exercise book!" ”

The classroom fell silent for a moment

“……”

The truth is the truth, but if you say it yourself, why do you feel like you want to hit him!

After Chen Fan leaves

"This Nima is too shameless!"

"It's like beating someone!"

"Routines, they're all routines!"

"The water in the city is too deep, I want to go back to the countryside!"

"A play in the city, a mountain people's laughter!"

"Speak human words!"

"You city people are so good at playing!"

……

Qiao Yingzi thought about it, and told her little sisters about it in the group of "Xianggong and his ladies"!

Xu Tingting: "Awesome, worthy of my husband!" ”

Lin Miaomiao: "Fortunately, the master and his old man transferred to Chunfeng Middle School, Yingzi ~ I feel sorry for you!" ”

Qiao Yingzi: "......"

Deng Xiaoqi: "This is too dark, if it weren't for Yingzi, your classmates, you would still be in the dark, hahaha, laugh and cry/laugh and cry!" ”

Shangguan Mi: "When I was in school, I had to film, and I hated the teacher leaving the workbook the most, I strongly condemn Xianggong's behavior, there are such brazen people in this world!" ”

Xu Tingting: "Agree! ”

Qiao Yingzi: "+1"

“+2”

“+3”

Chen Fan: "......"

I saw Chen Fan bubbling

He Jing: "Poof~ Xianggong is so helpless, but it's so cute, pinch your face upstairs!" ”

Qiao Yingzi: "Pinch together, no matter, brother~ I want you to help me make an exercise book!" ”

Chen Fan covered his forehead, shook his head, and walked to the office alone.