Li Dan is naturally happy to praise the other party.

After all, it's just a matter of touching the skin of the mouth, which is not only easy and easy, but also has no cost.

"Xian'er, you are amazing, thank you for giving me such a great chalk ......"

Lin Xian'er was as happy as a blooming flower, and introduced: "This is the special chalk for mathematicians produced by the feather coat stationery in Aichi Prefecture, an island country. The factory has been making chalk for more than 80 years and officially ceased production five years ago, in March 2015. Now this kind of chalk is used one less than one, and it is treasured by many mathematicians as a collector's item, and they are completely reluctant to use it. ”

Li Dan's heart suddenly twitched, looking at the only half of the chalk left in his hand, he felt distressed for no reason: "Xian'er, this kind of chalk should be very expensive now, how much is it......

Lin Xian'er said with a smile:

"There is no market.

The mathematicians in this world who can use this kind of chalk will not resell the chalk they have hoarded for money.

Still, don't worry!

When I heard the news that the chalk factory was about to cease production, I bought all the chalk in the hands of dealers in the market and in the stock of the chalk factory.

You just use this chalk to do mathematical calculations every day without eating, drinking, or sleeping, and you won't be able to use up this chalk in 100 years. ”

When Li Dan heard these words, he suddenly felt a little better in his heart.

However, this feeling of liking and distressing is really a bit torturous......

Yang Chaoran stood aside, looking at the mathematical formulas and symbols on the blackboard like reading a book from heaven, and asked stupidly: "Sister Xian'er, what are these things written by classmate Li Dan...... Do you have to learn these things in college in the future......

Lin Xian'er smiled faintly, pointed to the mathematical formulas on the blackboard and said: "These are all calculus mathematical analysis methods, and the so-called calculus is ......."

Lin Xian'er tried her best to explain the principles of calculus to Yang Chaoran in the most plain and easy-to-understand language, but the latter still looked at her with a cute face, not understanding at all.

"Sister Xian'er......

I see......"

At this time, Yang Chaoran's eyes suddenly lit up and said with a smile.

"Whew-you finally get it?!

Well, calculus is an interesting mathematical analysis, right?! ”

Lin Xian'er breathed a sigh of relief, in order to explain these things to the other party just now, she couldn't wait to use all the strength to breastfeed, which was more than 10,000 times more than 10,000 times more difficult than teaching Li Dan back then.

"I still don't understand calculus.

Moreover, I may not understand it in this life.

However, I did understand another thing.

You said in the imperial capital before that you were also a scumbag, you were lying to me-

It's not good for a child to tell lies, Sister Xian'er......"

Yang Chaoran blinked his big eyes and looked at Lin Xian'er with an embarrassed face, revealing a hint of sly gaze.

"Broken......

How did you forget this stubble......"

Lin Xian'er slapped her forehead and shouted miscalculation, she had to sigh that she was still not good at deceiving people, otherwise she would not be exposed by the other party so easily.

I have to say that in terms of IQ, Lin Xian'er is ahead of Yang Chaoran, I don't know how many grades.

But in terms of emotional intelligence and memory in some aspects, Yang Chaoran is a peerless rider, leaving Lin Xian'er far behind.

These two people are equal, each has its own merits, and neither of them can beat each other, let alone replace each other.

If they are a man and a woman, they are definitely the most complementary couple in the world.

It's a pity that they are both girls, and they have a magical fall in love with the same boy.

In addition to the coincidence, I always feel that there is a certain number in the dark.

In an instant, Lin Xian'er and Yang Chaoran actually had a mysterious feeling of the same heart.

first looked at each other, and then turned his little head in unison, looking at Li Dan, who was frowning and staring at the mathematical formula on the blackboard, at a loss.

"I felt like I had hit a dead end......

Calculus alone is not enough to solve the problem that I need to solve. ”

Li Dan sighed lightly, carefully put the little chalk head in his hand into the box, and shook his head helplessly.

Lin Xian'er stared at the blackboard for a long time, frowned and muttered:

"Dandan......

It is difficult to solve a practical complex problem with a single mathematical calculation.

Moreover, higher mathematics in the West has great limitations in solving uncertainty problems......

In fact, you can consider using a mathematical method that has been inherited in our country since ancient times. ”

"What methods can be used to solve the problem of uncertainty?"

Li Dan suddenly became interested.

"Have you heard of Zhou Yihe gossip?"

Lin Xian'er said with a smile.

"Zhou Yihe gossip? Isn't this used for divination, and can it also be used for mathematical calculations?! ”

Li Dan asked puzzled.

Lin Xian'er smiled and said: "Dandan, in fact, divination itself is an uncertain probability problem, and it is a mathematical calculation. If you are interested, there are similar books in the school library, and I can help you borrow them. ”

Li Dan looked at Lin Xian'er, and suddenly seemed to understand something: "Xian'er, is our school's library ......?"

Lin Xian'er nodded with a smile and said, "That's right, our school's library was funded and built by our Lin Group, and most of the books in it were also donated by our Lin Group." ”

Li Dan finally realized at this moment, no wonder the last time she borrowed those three aesthetic books, Lin Xian'er knew that there were those three books in the school library.

Since the libraries were all built by the Lin Group, and the books were also donated by the group, there was naturally a way to lend these books.

Yang Chaoran stood aside, naturally listening in a fog, he didn't understand what these two people were talking about, and he suddenly felt alienated.

Seeing that these two people finally finished speaking, Yang Chaoran hurriedly smiled and said to Li Dan:

"Li Dan.

I have some friends in the entertainment industry who have heard that you are a good doctor and want to consult you through me.

If you have time to lovingly help them, I can make an appointment for you.

Of course, the consultation fee is indispensable.

Since you charge me 100,000 yuan for the consultation, let's charge them 200,000 yuan......

If you think the price is low, it can also vary from person to person and from disease to disease.

They are all masters who are not bad for money, but they don't have the opportunity to find a real famous doctor for consultation. ”

When Yang Chaoran said this, Li Dan immediately thought that when he saw her for the first time, he was chasing her from the imperial capital to Donghai City Hospital, just to be able to ask Lin Xian'er's father Lin Fuming for a consultation.

From this point of view, famous doctors are still a scarce resource in the entire upper class.

Even high-ranking officials and nobles with extremely prominent status may not be able to make an appointment with a famous doctor like Lin Fuming without obstacles.

Not to mention celebrities and predators in the entertainment and business circles like Yang Chaoran.