Chapter 6

Wednesday.

In the early morning, Gu Lv just opened the door of the mathematics group office. Before he entered, he saw teacher Sun Ya coming from the English group office next door with a gust of fragrance and smiling.

"Teacher Gu, I brought some glutinous rice balls. Let's have a taste."

It can be seen that Sun Ya dressed up carefully today.

Her long, silky hair hung vertically over her shoulders, and her snow-white long sleeves clung to her body, outlining her exquisite curves. With her eye shadow and light blush, she instantly stunned several young male teachers in the mathematics group.

.

But at this time, Sun Ya's attention had long been focused on Gu Lu.

As a result, several young male teachers in the mathematics group could only watch with sorrow and anger as Sun Ya followed Gu Lu all the way to the desk.

Then, Sun Ya pulled up a chair and sat next to Gu Lu, holding her chin and watching Gu Lu eating the glutinous rice balls one bite at a time with a focused expression, feeling full of satisfaction.

Zhou Haihong came later this time. When he saw Gu Lu and Sun Ya sitting together, he walked over with some doubts.

"Teacher Sun, you are here to bring glutinous rice cakes again. Let me try and see if your craftsmanship has improved this time." Zhou Haihong stretched out his hand to get it.

But Sun Ya was even more quick-sighted and quickly pulled the plastic box containing the glutinous rice cakes aside and protected it in her hands.

"Teacher Zhou, I brought these specially for Teacher Gu today. If you want to eat them, I will bring them to you tomorrow!" Sun Ya said apologetically, holding the box of glutinous rice cakes tightly in her hands, as if to avoid Zhou Haihong.

The look of getting involved.

Zhou Haihong looked at Sun Ya and then at Gu Lu, who had an innocent expression on his face, and his heart ached instantly.

What a good little girl Teacher Sun was before!

Not only is she beautiful but kind-hearted, she also brings some small desserts made at home from time to time to share with the teachers.

But now, they have forgotten about the group of teachers who have worked together for more than a year, and are completely fascinated by Gu Lu. Even the desserts they brought are only enjoyed by Gu Lu.

well!

Zhou Haihong sighed, shook his head, walked aside, and began to play Ba Duan Jin.

"The first section of Baduanjin, holding the three radiators of heavenly principles with both hands, hey!"

…………

"Classmates, come to class. In today's class, you have only one task, and that is to solve the question I wrote."

It’s time for Teacher Gu’s class again.

After saying this, Gu Lu picked up the chalk and wrote a question on the blackboard.

[It is known that the function f(x)=alnx/x1b/x, the tangent equation of the curve y=f(x) at point (1, f(1)) is x2y-3=0.

(1). Find the values ​​of a and b.

(2). If when x>0 and x≠1, f(x)>alnx/x-1k/x, find the value range of k.】

"The first question is too simple. In order to avoid wasting time, I will give you the answer directly. a is 1, and b is also 1." Gu Lu directly wrote the answer to the first question on the blackboard, "Now what you need to do

, is the second question in solving this problem.”

"One thing I need to tell you is that there is not only one solution to this question, but what I need you to do is to diverge your thinking and come up with as many solutions as possible."

This question was accidentally discovered by Gu Lu on the Internet. He found it interesting, so he took it over and gave it to the students to try.

The reason why Gu Lu found it interesting was not that this question was so difficult. In terms of difficulty, this question was not even as good as the final question of the college entrance examination.

Instead, Gu Lu discovered that there were many different solutions to the second question. Counting them down, there were more than a dozen.

This is very interesting!

"If anyone has an idea, they can just come up and write it down on the blackboard. Okay, I'll leave the time to you." After Gu Lu finished speaking, he retreated to the side of the podium, moved a chair and sat down.

Almost as soon as Gu Lu sat down, a figure stood up from below and walked directly onto the podium with extremely confident steps.

Gu Lu looked sideways slightly and found that the first person to steal the spotlight was, as expected, the boy Bi Qi.

The students exclaimed as expected.

Bi Qi's speed is really too fast.

Some of them haven't finished reading the questions, but Bi Qi just... came up with a solution?

Sure enough, Bi Qi deserves to be a master with perfect scores in mathematics!

On the podium, Bi Qi smiled at Gu Lu with a satisfied face, picked up the chalk, and wrote on the blackboard with great vigor.

[From a=1, b=1, we know that f(x)=lnx/x11/x. Therefore, f(x)-(lnx/x-1k/xk/x)=1/1-x^2(

2lnx(k-1)(x^2-1)/x).

Function h(x)=2lnx(k-1)(x^2-1)/x,x>0, then h'(x)=(k-1)(x^21)2x/x^2.

(i) When k≤0, it is known from h'(x)=(k-1)(x^21)2x/x^2, when x≠1...]

Bi Qi's problem-solving steps are quite satisfactory. First, he constructs the function h(x) and takes its derivative. Next, he discusses the three cases of h(

x), discuss whether it is contradictory, and find the value range of k.

"So, at the end of this question, the value range of k should be (-∞, 0]!"

Bi Qi wrote the results confidently.

Gu Lu nodded, indicating that the answer was correct.

Below, the students looked amazed.

"Wow, Student Bi Qi is so awesome!"

"Worship the master of mathematics!"

"666, kneel down to the boss!"

Facing the compliments, Bi Qi waved his hands indifferently, "Ji Cao, don't 6!"

"By the way, teacher." Bi Qi turned to look at Gu Lu, "Can each person only write one solution?"

Gu Lu's lips curved, "If you can, you can write down as many solutions as you want."

Bi Qi picked up the chalk, thought silently, and then put it down again.

"Oh, forget it, let's leave some opportunities for other students, otherwise it will be too much." Bi Qi shook his head, sighed, and sat back in his seat.

Gu Lu watched Qi's show-off with a speechless expression.

This guy...

Gu Lu felt like he didn't know how to evaluate it.

He rubbed his brows and said helplessly, "The next student who has an idea can come up directly."

Half a minute later, Ma Zhengxuan came up with a draft book and wrote down his own ideas for solving the problem.

Ma Zhengxuan's problem-solving idea is also a conventional solution. It uses the second derivation of the function to conduct analysis on a case-by-case basis. In terms of specific steps, it is more complicated than Bi Qi's solution.

It is indeed a bit difficult for high school students who have not been deeply poisoned by exam-oriented education to allow them to think beyond common sense.

In addition to Bi Qi and Ma Zhengxuan, another student in the class with good math scores wrote down his own solution.

After that, no classmates came up to try it.

Seeing that there were still ten minutes until the end of get out of class, Gu Lu stood up helplessly.

I have no choice but to let me appear!

"I think time is running out. Since the students don't have any new insights, let me tell you a few solutions I have come up with." Gu Lu said loudly, "You guys, watch and listen!"
Chapter completed!