Back to the 80s Machinery Factory

Chapter 390 Math is too hard!
Mr. Zhou, who taught advanced mathematics at the school, was an associate professor in the mathematics department, but was transferred to teach in the economics department.

"Today we'll talk about the definition of a limit..."

Teacher Zhou wrote with chalk, his strokes flowing like dragons and phoenixes on the blackboard.
Chen Luyang sat at the bottom of the classroom like someone with intellectual disabilities, memorizing everything the teacher said!

Now he finally understood why students frantically copied down the lectures when the teacher was lecturing on economics.

I really can't understand it...!
If you don't try your best to memorize everything, then when you look back, you'll find that you don't know anything at all.

While he was frantically copying from the blackboard, very few of the students around him actually started writing!

If you don't write anything, then forget it.

Things I can't even understand myself.

Zheng Zhe, that chubby boy, didn't even open the book; he just sat there and listened.

He would listen, but occasionally he would hum in disapproval, as if he disagreed with the teacher's teaching.

He would occasionally doodle something on a piece of paper.

What is he writing?
Chen Luyang was curious and wanted to take a look at the head.

Before he could even stick his neck out, the blackboard eraser slammed onto the blackboard with a "duang," making an evil, ear-piercing sound!
"Don't get distracted, look at the blackboard!"

Teacher Zhou shouted angrily!

"This place is very important!!!"

"You don't understand, so why aren't you listening carefully!"

Grass……!
Chen Luyang broke out in a cold sweat.

This week, the teacher is definitely talking about himself!

...What the hell? How did he know he couldn't understand it?
He quickly pulled his head back, and his pen began to frantically jot down notes in his small notebook again.

"...At this point, how do we construct δ? This is the key point, everyone please pay attention."

Teacher Zhou wrote formulas on the blackboard with a series of scribbling sounds.

Like a recorder, Chen Luyang frantically jotted down Teacher Zhou's words and the formulas on the blackboard into her notebook.

There were several times when Chen Luyang simply couldn't keep up with the copying.
Just as I was about to slip away, Teacher Zhou glanced at me.

Startled, Chen Luyang hurriedly began to memorize the notes again.

By the end, my right wrist was sore.

finally! ! ! !
The get out of class bell rang.

Chen Luyang felt as if she had been freed, her mind completely blank.

He sat in his seat.

A group of people surrounded Teacher Zhou, bombarding him with questions from all sides.

Chen Luyang also wanted to ask...

But he didn't know what to ask...

Absolutely none! No clue whatsoever!
Math is too difficult.

He looked down at the small notebook filled with notes.
Although I wrote down the content,
But he didn't understand where this thing came from, why it came, or where it was going after it arrived.

Seeing the relaxed and carefree expressions of his classmates,
For the first time in her life, Chen Luyang felt a slight wavering and doubt about her own intelligence.

Am I a complete idiot...?

Why can't I understand it?
Unfortunately, Chen Luyang ran into Teacher Zhou right when she went out!

Before he could even say hello, Teacher Zhou blurted out:

"You're taking notes really diligently!"

wipe!!!!

Chen Luyang's face instantly turned bright red.

Before anyone could answer, Teacher Zhou had already strode away with an air of nonchalance.

Damn... I feel humiliated.

woo woo woo woo
……

in the afternoon,

Furious and resentful, Chen Luyang took her textbook and the lecture notes she had taken during the day and went to the classroom to study.

I'm ready to conquer this small nut of advanced mathematics all by myself!

But as I looked at it...

The raging fire of anger gradually weakened, grew weaker and weaker, and finally turned into frustration...

What the hell is all this?!

He looked down at the page on the definition of limits in the textbook and stared at the “ε-δ language” for a good ten minutes.

"For any positive number δ, ε corresponds to... what does it exist? How does it exist?"

Chen Luyang tried to piece together some logic from the textbooks and notes, but the more she tried, the more confused and disorganized it became!
"This isn't looking for a partner, it's looking for a ghost!"

Chen Luyang slammed the book shut, her fingers trembling as she anxiously scratched her head.

My heart is filled with endless regret!
I must be crazy to have chosen a major that involves advanced mathematics!
If freshman year courses are this difficult, how will I get through the next four years?!
The more Chen Luyang thought about it, the more his head ached.

Just as he was about to close the book and go play basketball for a while to clear his head,
But to his surprise, he saw the chubby boy right behind him.

"Eh~"

Chen Luyang turned her head, lowered her voice, and asked curiously in a soft voice, "What did you write in your notebook during class?"

Zheng Zhe asked in a low voice, "Which class?"

Chen Luyang: "Advanced Mathematics!"

Advanced mathematics?

Without hesitation, Zheng Zhe handed the notebook directly to Chen Luyang.

Chen Luyang thought Zheng Zhe was going to show her the notes, and excitedly flipped them open!
ah!?!?!?!
Chen Luyang stared at Zheng Zhe with her mouth agape in astonishment.

"Is this all you wrote?"

Chen Luyang pointed to the dozens of hastily drawn five-pointed stars on the notebook, feeling her already numb mind become even more numb.

"That's all I can draw." Zheng Zhe put his notebook away.

Chen Luyang was speechless: "I thought you were taking notes and highlighting key points!"

Zheng Zhe was puzzled: "What's there to remember? It's all written in the book. I get sleepy in class, and when I'm really sleepy, I draw a five-pointed star to distract myself."

Grass! ! !
At that moment, Chen Luyang had murderous intent.

I can't understand anything myself, and even after frantically copying notes, it's still difficult to have an epiphany.

As a result, someone got bored in class and started drawing five-pointed stars to stay awake...!
He glanced at the chubby boy with a complicated expression.

Strictly speaking, the chubby boy lost some weight after starting school.

The school food was too bland, and Zheng Zhe was never satisfied with his meals. Every day, watching him eat steamed buns, he looked utterly hopeless.

"Then tell me about it!"

"Okay! What should we talk about?"

Zheng Zhe didn't notice the murderous intent in Chen Luyang's eyes and craned his neck to ask.

"What exactly is this definition of a limit?!" Chen Luyang rubbed his temples.

Zheng Zhe picked up his pen and quickly sketched a small picture on the paper:
A horizontal axis, a vertical axis, a curve, a point a, a small interval, and a small ε.

"You used to boil water when you were a child, right?" Zheng Zhe asked.

Chen Luyang nodded.

Zheng Zhe asked, "Does the kettle lid start to pop open just before the water boils?"

Chen Luyang nodded quickly.

Zheng Zhe continued, "Although the water temperature is not exactly 100 degrees, it is close enough to 100 degrees."

"Approaching a certain value, but not actually reaching it, this 'approaching' state is the limit."

Chen Luyang hummed in response, seemingly understanding a little.

Zheng Zhe wrote a series of arrows on the paper indicating "x is close to a" and labels indicating "f(x) is close to L", and then began to speak:

"The kettle starts bubbling and steaming before the temperature actually reaches 100 degrees."

"Therefore: as x gets closer to a, f(x) also gets closer to L - this L is the limit."

Chen Luyang pointed to the small diagram on the paper and tentatively asked, "Is ε the gap? Is δ the range?"

Zheng Zhe nodded: "Yes, that's exactly it."

Chen Luyang's eyes widened: "That's it?!?!" "...Then what was Teacher Zhou doing with all those δ and ε symbols twisting and turning for half the lesson?"

“That’s just formalistic expression,” Zhao Lixin, sitting next to him, interjected with a smile.

"Mathematics is all about precision; even if you understand it in your mind, you still have to be able to express it clearly in words and writing."

The key thing is, I don't understand!

Chen Luyang looked at the chubby boy and Zhao Lixin with a bitter expression.

It's really irritating to see people compare to each other.

Everyone else complains that the teacher is too long-winded, but I can't understand anything at all.

"If only we could go back to the Middle Ages," Chen Luyang murmured.

Zheng Zhe couldn't understand Chen Luyang's thought process, and a look of doubt appeared in his eyes.

"Go back to the Middle Ages and burn all the mathematicians at the stake!" Chen Luyang said with hatred and murderous intent in his eyes.

Zheng Zhe: ...

Zhao Lixin: ...

After venting my emotions, I learned what my limits were.

Regardless of whether you understand anything else, that's all for today's advanced mathematics lesson!
If he keeps reading, he'll lose himself completely.

"Let's go play ball?" Chen Luyang urged the chubby boy to go play ball with him.

“…Okay! Let’s go.” Zheng Zhe was also at an age where he loved to play and have fun, and he felt bored sitting in the house for too long.

"Old Zhao, wanna go? Let's play ball?" Zheng Zhe called out to Zhao Lixin.

Zhao Lixin hesitated.

He hasn't finished reading the book yet.

However, before Zhao Lixin could even refuse...

Chen Luyang, a cunning and despicable person who neither wanted to learn nor wanted others to learn, directly tempted him with flamboyant gestures:
"Let's go! Let's play for ten minutes, warm up, and then come back and watch."

Zhao Lixin was successfully tempted: "Let's go!"

Seeing that one person had been tempted away, Chen Luyang turned around and started urging another:
"Brother Jiang, let's go! Want to play some ball?"

Jiang Feng decisively refused: "I'm not going, you guys go. I have to go to the school's Party Committee office in a bit."

"What are you going there for?" the chubby boy asked, puzzled.

"I'm going to have a chat with the Party Secretary." Jiang Feng glanced at Zheng Zhe with a mischievous grin.

"gone!"

After saying that, Jiang Feng mysteriously walked out of the classroom.

"What is he going to do?" Zhao Lixin asked, puzzled.

"He went to the school's Party committee to try and get a spot for our class to join the Party."

Chen Luyang called to the two of them, "Come on, let's go have some fun!"

……

Although many students study diligently at school, there are also quite a few who exercise and stay fit.

If you're young, have good legs and feet, and like to get active, then play soccer, basketball, or go for a run.

Those who are a bit older go to play table tennis or take a walk.

People were exercising near the parallel bars and horizontal bars, and students were everywhere on the playground.

When Chen Luyang and his two companions arrived at the basketball court, there were already people playing basketball under several hoops.

Just as they were about to decide which faction to join, a voice rang out:
"Chen Luyang, this!"

Chen Luyang subconsciously looked toward the sound.

On the court, Cui Shaojie, wearing a white vest, raised his right hand to greet him.

"Together?" Cui Shaojie called out.

"Together!" Chen Luyang shouted back happily.

Cui Shaojie held the ball with both hands, threw it with a backhand, and threw it directly at Chen Luyang.

Chen Luyang took the ball, slapped it a few times, and dashed onto the court!
……

This game was...exhilarating!
Although Cui Shaojie and his team played quite well, they were simply too tall and had a significant height advantage.

Chen Luyang and Zhao Lixin's height makes them virtually invincible on the court.

In addition, the chubby Zheng Zhe charged around recklessly, putting the philosophy students on the defensive.

After finishing the game,

The group ate at the cafeteria, took a shower, said "See you in a bit," and went back to their dorms to get their bags.

Tonight's evening class is still on political economy.

When Chen Luyang changed into a new outfit and arrived at the classroom with her schoolbag, the room was almost full.

kindness?
Chen Luyang subconsciously walked towards the seat that Gao Xiaolin usually occupied, only to find that the second row had been taken by someone else.

Gao Xiaolin and Tao Runze sat in the middle of the classroom.

Seeing Gao Xiaolin waving, Chen Luyang was about to walk over and sit down with her classmates when...

The students in the front row disagreed.

"Chen Luyang, there's a place here!!!"

"Xiao Chen, there's room right here!"

"Chen Luyang, sit here!"

……

Chen Luyang didn't recognize any of the people who were speaking.

I reckon they're all philosophy students.

"Thanks, classmate. My roommates saved me a seat."

After gratefully speaking to the students in the front row, Chen Luyang rushed over to Gao Xiaolin's row and sat down in the empty space.

"Why are you sitting in the middle today?" Chen Luyang asked curiously, taking out her pen and notebook.

"We couldn't beat them today." Gao Xiaolin rolled her eyes.

As the group was talking, the school bell rang.

Teacher Lian, carrying books, once again walked into the classroom right on time.

There were no pleasantries, no introductions, he simply stood on the podium, opened his lecture notes to the first page, and the first thing he said was:

What did everyone eat for dinner?

"Steamed buns~"

The classroom was filled with cheerful responses from everyone.

"You all ate steamed buns?" Teacher Lian's usually fiery and cool face rarely showed a smile.

He glanced at the classroom full of students and laughed, "I also ate steamed buns for dinner."

Everyone in the classroom laughed.

"Last time we talked about how Cui Shaojie found the first steamed bun the most delicious. The eighth one was okay, the ninth one made him choke, the tenth one was uncomfortable, and the eleventh one he couldn't eat."

"Right... Cui Shaojie?"

Hahahahaha

The classmates laughed again, and Cui Shaojie sat down in his seat, grinning foolishly along with everyone.

Teacher Lian turned around and wrote on the blackboard with chalk: > MU↓ (diminishing marginal utility)

"The more you eat, the less satisfaction each bun brings you, until there is a critical point where the satisfaction it brings is exactly equal to its price. After that, it becomes a struggle and a waste."

As he spoke, Teacher Lian wrote another formula on the blackboard: > MU / P = equilibrium.

"By dividing marginal utility by price, when you eat the last worthwhile bun, every penny you spent is of equal value and weight. The underlying principle is consumer equilibrium."

As Teacher Bian spoke, he wrote "consumer equilibrium" and a long string of English explanations on the blackboard.

After writing, Teacher Lian instinctively asked Chen Luyang, who was in the second row, to stand up and read and explain the meaning of the two English words.

But when he pointed to the familiar second row, he found that the seat where Chen Luyang usually sat had been taken by someone else.

"Chen Luyang didn't come to class?" Teacher Lian suddenly asked.

"Teacher! I'm here." Chen Luyang was so startled that she quickly raised her hand and stood up.

I came to class so diligently, how could I almost be considered absent!
(End of this chapter)