I failed a course, and the system became my study supervisor.

Chapter 6: How to write the word "Hui" in Fennel Beans

The next day, Xu Ling's cousin finally came.

I still came early in the morning, just like I was going to school.

According to my second uncle's instructions, I only need to supervise the child while he does his homework, check it for him after he finishes, and teach him the wrong questions.

It seemed that this was not so bad, so Xu Ling breathed a sigh of relief. He let his cousin do his homework while Xu Ling began to study the supplementary materials.

"Fourier analysis provides an important tool for studying theoretical problems such as the existence, uniqueness, and stability of solutions to partial differential equations..."

Wow! Xu Ling was very excited. He had never expected that the content summarized in just one chapter of the mathematics course would have such high application value.

However, before he could continue to dig deeper into this small gold mine, Xu Ling heard his cousin's childish voice:

"Brother, I've finished my homework! Show it to me!"

Xu Ling readily agreed. Isn't checking homework a very easy job?

But when he set his eyes on his cousin's exercise book, Xu Ling realized that he was really wrong.

"No! Why is 158-68 equal to 0?"

"I calculated it!"

"Show me how you calculated it!" Xu Ling was shocked.

只见堂弟拿出草稿纸，列起了竖式。然后徐凌眼睁睁看着他写了一个8-8等于0和5-6等于0。

Xu Ling immediately interrupted him: "Why does 5-6 in the tens place here equal 0?"

My cousin answered innocently and matter-of-factly, "5-6 isn't enough to lose weight?"

"If it's not enough, can't you borrow one from the hundreds place in front?"

"Will it borrow?"

"How about you ask?"

"Then I'll ask it."

Xu Ling exploded! You really need to ask!
The key point is that this is not his biological brother, so Xu Ling didn't dare to say anything harsh. It took him a lot of effort to explain it to him clearly.

Xu Ling couldn't help but sigh: I feel so tired!
However, at this moment, the system prompt sounded at an inopportune time:

"A new task has been released, please check it!"

Isn't it just teaching a primary school student arithmetic? How can it trigger a quest?
Xu Ling opened the taskbar in confusion.

【Ordinary tasks

(1) Library check-in (suspended)
……

(2) (Fun Task) How many ways are there to write the character "卉" in fennel beans? As a college student in the new era, how can I not show off my knowledge? Please use simple language to explain the idea of ​​calculus to my cousin.

Completion reward: 50 Diligence Points.

Failure penalty: deduct 30 study points.

Can it be rejected: Yes. 】

No!

Me? Show off?

He? Calculus?
Isn’t this a fantasy?

But those 50 points of diligence are as tempting as a beauty just out of the bath!

It's done!

Xu Ling made up his mind and accepted the task. At worst, he would owe him 30!

"Brother, let me tell you something interesting." Xu Ling said to his cousin with a smile.

"What?" my cousin asked curiously.

"Um... a math problem." Xu Ling touched his nose.

"I don't want to listen, you're just a turtle chanting sutras." My cousin shook his head like a rattle.

"After you listen, I'll play Pesticide with you!" Xu Ling released his ultimate move.

It really worked. The cousin immediately looked at Xu Ling seriously. "Brother, do you know what area is? It's a shape, a rectangle, a triangle, it has a certain size. For such regular shapes, it's easy to calculate their area." Xu Ling hesitated for a long time before speaking slowly.

"But if a shape looks strange, we can't simply calculate its area. What should we do then?

We also have a way. We divide it into many small rectangles, calculate the area of ​​these small rectangles, and add them up to get the total area.

That's differential and integral calculus!"

Xu Ling racked his brains and finally expressed the idea of ​​calculus in simple language.

After taking a breath, Xu Ling looked at his cousin hopefully: "Do you understand?"

"I understand!" The cousin nodded seriously.

"Is it true? Tell me about it?" Xu Ling was very excited.

"It's just about turning the big rectangle into a small rectangle, and then turning the small rectangle into a big rectangle." My cousin said confidently.

Very good! More or less.

Xu Ling generously handed the phone to his cousin. After listening to the familiar opening sound effect, the system finally responded.

"Ding!"

"Mission completed! Reward: 50 study points!"

50! Seeing his study points soar by 50, Xu Ling was extremely excited.

He had never fought such a rich battle!
However, Xu Ling turned around and was a little confused. He had caught the overwhelming wealth, but how could he use it?

Should I save it and wait for the next draw?

Or use it in focus mode?

This is really a question worth thinking about.

It is possible to win an amazing prop or even a drawing in a lottery, but it is also possible to win a piece of junk similar to the one you won last time.

But it’s different if you just turn on focus mode.

One word, steady!

It is directly foreseeable that the focus mode will definitely help Xu Ling improve the efficiency and gain of reading materials.

To be on the safe side, Xu Ling finally chose to spend his study points on the focused mode first.

This decision did not disappoint Xu Ling's expectations. With the help of focus mode, Xu Ling's efficiency increased by more than double, and his understanding of various concepts also deepened a lot.

For example, Xu Ling has his own understanding in proving the conjecture of global solution with small initial values.

For partial differential equations involving time and space variables, interpolation analysis can be performed in time and space respectively.

For example, when proving the existence of a global solution with small initial values, the solution is first discretized in time to obtain estimates of the solution at different time steps, and then an estimate is obtained in continuous time through interpolation methods.

Spatially, solutions in different regions or at different resolutions are interpolated to obtain a consistent estimate of the solution for the entire space, thereby proving the regularity of the global solution with small initial values.

However, this understanding is only a directional thought. Xu Ling has no confidence in whether this method can be proven.

After all, if you can easily think of it, why can't others think of it?

And this conjecture is still a conjecture, which means that this plan is either not feasible or has difficulties.

Of course, Xu Ling did not expect that he could solve such a difficult problem with just a few days of superficial research.

In the next few days, Xu Ling's cousin came every day.

After feeling the academic shock brought by the primary school students, Xu Ling felt a strong admiration for primary school teachers.

However, the system hasn't triggered any interesting tasks in the past few days, and Xu Ling couldn't help feeling a little regretful.

That’s 50 study points each!

A week before the Spring Festival, my cousin didn't come again.

Although the environment was quiet, Xu Ling did not relax. He still chose to seclude himself and immersed himself in crazy attempts to prove various conjectures.

……

(End of this chapter)