My textbook turned into a beautiful girl

With Mr. Liu's teasing remark, the once quiet classroom was completely transformed into a sea of ​​joy.

An Yi forced a smile, trying to ease the awkwardness. However, as the one who had caused this sea of ​​joy, he simply couldn't manage a laugh.

Why isn't there a mechanism to prevent addiction to studying? This is terrible!

"However, I see that this student's attitude towards learning is very serious, so you can be considered to have successfully checked in."

Teacher Liu had actually noticed An Yi long ago.

There aren't many students willing to sit in the front row during class, and even fewer are willing to keep writing and studying during breaks without even taking out their phones.

"Also, considering the brotherhood between you friends, I can give you another chance regarding their sign-in... Have you ever seen a TV show called 'Open the Door to Good Fortune'?"

An Yi thought for a moment: "Is it that game where you have to guess the song title based on the beat of the intro?"

"Yes, but this is an advanced mathematics class, so of course we need to make some reasonable changes... Let's play a quiz game."

Teacher Liu said with a smile.

"Answer one question and you can choose one friend to sign in. Answer the second question and all three of your friends will sign in. If you answer the third question... then everyone will have successfully signed in for today's roll call! How about it, want to give it a try?"

"Looking at your thick eyebrows and big eyes, I thought you were a kind person, but I didn't expect you to be so treacherous!" An Yi thought to himself.

Actually, if there were only the first two rewards, it wouldn't matter whether An Yi could answer the questions or not, or whether he chose to answer them or not. His three adopted sons in the dormitory wouldn't blame him for this.

After all, they all knew An Yi's level; he usually copied their calculus assignments!

But when Teacher Liu added the last reward, the situation immediately changed.

As the game rules and rewards were announced, the classroom erupted in cheers. Even those who had been playing on their phones were drawn in by the noise and, after asking around about the rewards, joined in the commotion.

The world may lack many things, but it can never lack people who can have fun!

"How will you choose?"

Beside her, the girl's voice was exceptionally clear even in such a noisy environment, and the sunlight outside the window reflected in her eyes, making her breathtakingly beautiful.

"Should we try, or give up?"

"Giving up without even trying..."

An Yi pouted, "You'll be very disappointed, won't you?"

"Well... I just think that if it works, it works; if it doesn't, it doesn't."

After thinking for a moment, the girl replied, "But how will you know if you can do it if you haven't even tried?"

"So this isn't even a multiple-choice question!" An Yi complained.

"Of course."

The girl smiled faintly, "You don't have to be like this."

"That's impossible!" An Yi replied decisively.

If we don't do it this way, won't we lose favorability?

Since if I try and can't answer, at most I'll just lose face, but it won't hurt me! So, there's no need to think too much about which option to choose.

"What's your decision?"

From the perspective of Ms. Liu, who was standing to the side, An Yi had only experienced a brief period of hesitation and difficulty, so she urged him on.

"I'll take it! But teacher, this puts me in a difficult position."

An Yi stood up with a wry smile. Since he had already made his decision, he felt a sense of reckless generosity and acted without restraint, even preparing to make a joke.

"Oh? What do you mean by that?" Teacher Liu asked with a smile.

"Think about it, I came here to complete the quiz and sign in for my three roommates. When we get back, they'll all have to call me godfather. That's only right."

An Yi stepped out of her seat. "But you added a reward for the third level. If I give that to all the students who didn't come, how am I supposed to send out red envelopes during holidays?"

Upon hearing this, the entire lecture hall burst into laughter, including Teacher Liu.

Teacher Liu laughed for a while, then raised his hand to gesture for everyone to be quiet before getting down to business. "Don't make any promises you can keep. You have to actually be able to pass them first."

As he spoke, he began writing problems on the rising blackboard.

The first question is ∫1/（x^6）dx.

"Really?"

An Yi was stunned for a moment, then looked at Teacher Liu in disbelief. "Teacher, once it's written, there's no going back. It can't be changed!"

This is a freebie, the kind of question that even a high school student could answer easily at a glance... Could it be that Teacher Liu was just using this interactive game to liven up the classroom atmosphere and didn't intend to make things difficult for him?

"Don't rush, this is only the first question." Teacher Liu still had that smiling expression.

An Yi had a bad feeling, but he had no choice but to pick up the chalk and write the answer on the blackboard since things had come to this point.

∫1/（x^6）dx=-1/（5x^5）+C

"Very good. So, will you choose to stop here or continue? Oh, and I should mention in advance that the rules of this game are the same as 'Open the Door to Good Fortune.' If you choose to continue but fail to answer the question, all the previous rewards will be forfeited," Teacher Liu asked.

"Teacher, it's not scarcity that's the problem, but inequality. Please don't joke around." An Yi's eyes twitched slightly.

If it really ends here, and we just have one spot and it doesn't matter who we choose, wouldn't that be a modern evolution of the "two peaches kill three warriors" scenario?

Teacher Liu is indeed cunning and treacherous!

"You've chosen to continue, right?"

Teacher Liu smiled and confirmed it again.

"Yes, yes, come on!" An Yi said with a resolute expression, as if he were preparing to bravely sacrifice himself.

The main problem is that there's no other way... The girl who embodies "Advanced Mathematics" is standing right next to him watching right now. Since he's already on stage, he might as well take the opportunity to perform well!

"Here I come."

Teacher Liu casually wrote down the second question.

∫1/（x^6+1）dx

The only difference was that the denominator of the integral in the first question was increased by 1, so it didn't seem too difficult at first glance. A few students in the classroom even voiced their dissatisfaction, probably thinking that Teacher Liu was deliberately making things easier for them.

"hiss……"

Among the students in the first few rows, several top students gasped in surprise after just one thought about the question.

Teacher Liu smiled again.

"He seems pretty smug."

The girl next to An Yi asked, "What are your thoughts?"

"That's normal, isn't it? After all, they're teachers... how could they so easily let a student who skipped their class off?"

An Yi expressed his understanding of this.

"but……"

He looked at the question in front of him and squinted slightly.

"How about it? I can give you one more chance. Choose to stop here or continue?" Teacher Liu asked impatiently.

He looked at An Yi, seemingly anticipating that An Yi would choose to give up with a troubled expression.

To Mr. Liu's surprise, after he asked the question, An Yi seemed to suddenly come to her senses, glanced at him, smiled apologetically, and spoke.

"Teacher Liu, I think I can do this problem a little bit..."

Teacher Liu: "???"

Before he could react, An Yi had already picked up the chalk and started writing on the blackboard.

第一步：(x^6+1)=(x²+1)(x^4−x²+1)

第二步：1/(x^6+1)=(x^4−x²+1-x^4+x²)/((x²+1)(x^4−x²+1))=1/(x²+1)+(x²-x^4)/(x^6+1)

第三步：前半部分∫1/(x²+1)dx的结果为arctanx+C₁，下面计算后项∫(x²-x^4)(x^6+1)dx……

Step 4...

Step 5...

As An Yi wrote down the first step, the once noisy lecture hall gradually quieted down.

No one is a fool. After seeing An Yi's first step, the students present all realized that this thing was not as simple as it seemed.

As for the second and third steps... apart from the top students in the first few rows and a few others who could keep up, the reactions of everyone else, especially the fun-loving ones, all pointed to four words—

I was terrified!

Teacher Liu looked on in surprise as An Yi gradually approached the correct answer.

As a calculus teacher, Mr. Liu certainly knew the true value of the seemingly simple integration problem he set. It's safe to say that if he hadn't explained it and had simply thrown it into this year's final calculus exam, over 99% of students would have failed it!

Of course, this wouldn't be a problem for a math major's final exam. However, this is an engineering major, where they study "Advanced Mathematics" instead of "Mathematical Analysis," and Jingjiang University is just a non-985/211 university. Therefore, the difficulty of the problem ∫1/(x^6+1)dx can be described as extremely high.

Adding one to the denominator results in the same value being lost. This is a timeless proverb in integral problems!

It's fair to say that when Mr. Liu set this question, he never considered the possibility that An Yi would be able to answer it. His reasoning was simple... truancy is truancy; why would he let those students off so easily?

Therefore, even though An Yi initially claimed to have a little bit of knowledge and started writing, Teacher Liu didn't really pay much attention. He thought An Yi at most had some ideas and was unwilling to give up so easily, so he wanted to give it a try. But that's okay, this is mathematics.

If you don't know math, you just don't know it; you can't force yourself to do it.

But to his surprise, An Yi actually succeeded.

This guy's level of advanced mathematics, at least his integration level, has far exceeded the requirements of the course "Advanced Mathematics"!

"Even in engineering majors, there are bound to be people who are good at math. I was just overlooking that..." Teacher Liu thought to herself, already having a plan in mind.

Just as Teacher Liu was pondering, An Yi had already smoothly written down the final answer.

∫1/(x^6+1)dx=1/2arctanx+1/6arctan(x^3)+ln|(x+1/x+√(3))/(x+1/x-√(3))|+1/4√(3)+C

The classroom was so quiet you could hear a pin drop.

"teacher?"

An Yi held the chalk and looked at Teacher Liu.

"Not bad...very good...excellent!"

Teacher Liu realized what was happening, looked at the calculation steps that filled most of the blackboard, and kept giving higher and higher evaluations. Then she looked at An Yi and smiled.

"Congratulations, you can now become the godfather of your three roommates."

The audience members and onlookers below the stage were immediately in an uproar. Just seeing An Yi's calculation steps made them feel a headache, but they didn't expect the result to be correct.

All I can say is, no wonder he's a big shot sitting in the front row! His credentials are truly impressive!

Teacher Liu raised her hand again, gesturing for everyone to quiet down. Only then did she compose herself and reveal that malicious, smirking expression once more.

"Very good. So... would you like to continue with the third question? Just so you know, the third question is very difficult. After all, it involves so many students, I can't let you succeed easily."

After saying this frankly, Teacher Liu made a joke.

"Besides, didn't you already say that if they actually answered correctly, all those adopted sons would go bankrupt just from giving out red envelopes during holidays!"

Normally, Teacher Liu wouldn't have needed to make that joke, but for some reason, he had a bad feeling... An Yi solved the second problem too quickly, so quickly that it didn't seem like he had gone through any thought process.

This indicates that An Yi's "accumulation index" is a bit high, and may even exceed the course requirements of "Advanced Mathematics"!

In this situation, Teacher Liu couldn't afford to go easy on An Yi any longer. Mainly, he felt this had nothing to do with "helping others achieve their goals"—how could everyone actually sign in successfully? When he announced this reward, he didn't expect An Yi to actually be able to do it!

Therefore, if An Yi really decides to continue, then the questions he sets must be more difficult, but not so difficult that they obviously require the use of knowledge beyond the syllabus... With this in mind, Teacher Liu already had a plan and was just waiting for An Yi's decision.

"Don't be afraid, An Yi, I'll crowdfund the money for you later!"

A classmate of An Yi, who knew An Yi, hid in the crowd of students and shouted, which caused another burst of laughter.

"An Yi, right? How so?" Teacher Liu finally learned An Yi's name.

"We've come this far, we have to give it a try no matter what, teacher?"

An Yi took a deep breath. To be honest, he felt he was getting a little arrogant. Teacher Liu was clearly up to no good. But perhaps it was the confidence brought by his increased calculation ability, and the presence of a pretty girl watching... so be it!

If you don't take advantage of your youth to be ambitious, when will you? You won't have the chance to be ambitious when you're old!

"I choose to continue!"

"it is good."

Teacher Liu didn't try to persuade him any further. He picked up the chalk and wrote the third question on the blackboard.

∫1/(x^5+1)dx

It's still a fairly simple question, and it seems to be just the second question with X raised to a power of 1 less... The change doesn't seem to be that big?

At least that's what the audience, including the entertainers and onlookers, thought. This time, even the other high-achieving students in the front rows shared the same sentiment; they were all somewhat puzzled. The problem seemed solvable using the same method, and An Yi had already solved the second problem.

Could it be that Teacher Liu is really going easy on us this time?

"Oh no, we're doomed."

An Yi took a deep breath.

This time, even with his [computational ability +1], he was at a loss for ideas for a moment.

He subconsciously glanced at the girl beside him.

"This is way beyond the scope of the curriculum, isn't it?"

"In terms of its fundamental nature, it's not beyond the scope of the curriculum, and it can still be calculated using the same method. However, it can also be interpreted as being beyond the scope of the curriculum for you because you don't know some key concepts, so the amount of calculation becomes extremely large, so large that you can't calculate it with your current computing power."

The girl smiled and explained, "Do you need help?"

"Is that okay?" An Yi asked, somewhat surprised.

"Okay, but you have to promise me one thing afterwards." The girl was still smiling.

For some reason, An Yi had a feeling that "this smile seems a bit sinister," but at this moment he could not hesitate and could only nod in agreement.

So the girl stepped forward and extended her right hand.

An Yi subconsciously reached out her hand.

Touch your hands together and hold them.

It feels warm and soft to the touch, like warm jade.

At the same time, a light screen popped up in front of his eyes.

[You have received a gift from Mathematics: Advanced Mathematics]

You have gained [Knowledge - Golden Ratio]

You have obtained [Knowledge: Palindromic Polynomial]

[You have achieved the milestone: First physical contact]

You have gained [Memory Ability +1], permanently!