After Qingshuang came in, she didn't speak, just looked at Yang Xuan quietly.

Yang Xuan was a little helpless, and said, "Are you so well-informed? I just came back, and you came." ”

Qingshuang looked at him for a long time and said, "I opened this inn, what do you say, and I have been waiting for you here." ”

Yang Xuan sat on the chair and poured himself a cup of tea: "Is there something wrong?

Qingshuang frowned and looked at him, "Why did you do this?"

Yang Xuan smiled: "It's nothing, I just think that if you do Qingxue's colt like this, you will suffer a little loss." ”

Qingshuang's face was full of speechless expressions: "Do you think you have suffered a loss when you are a concubine? Qingxue's national strength is several times that of Yan Kingdom, and there are countless wealth, you become a Qingxue concubine, and when the princess ascends the throne and becomes the emperor in the future, you are under one person, above ten thousand people, you still feel that you are at a loss?"

Yang Xuan took a sip of tea and said noncommittally: "Your tea here is good." ”

Qingshuang didn't understand what he meant.

Yang Xuan continued: "But I still like to drink a little dark night fragrance, I'm used to drinking it, and I can't change my mouth." ”

Qingshuang seemed to understand what he meant.

"By the way, who has become a colt?" Yang Xuan asked.

"Yan Yiyan, no matter how knowledgeable and martial arts, except for you, he will not be the second choice. Qingshuang said.

"Then why don't you hurry back and guard him?" Yang Xuan said casually.

"Did I say I was a princess?" Qingshuang said lightly.

"Whatever!" Yang Xuan shrugged: "What are you looking for me for?"

Qingshuang glanced at him again, she really couldn't figure out what this man was thinking, and after a while, she took out a simple ring.

"Storage ring?" Yang Xuan was stunned.

"Well, it's a storage ring!" Qingshuang didn't deny.

Yang Xuan smiled, this kind of ending is really good, he doesn't have to be a colt, and he also got a storage ring.

"Is it true or false to measure Zhou's straightness?" Qingshuang asked him one last time.

"It's true. Yang Xuan did not hesitate and replied directly.

Qingshuang threw the ring to him, then got up and went out, and after walking a long way, a sentence floated in: "You still owe a few days, don't forget to settle the bill." Well, there will be a period later!"

Yang Xuan then remembered that he only took out twenty taels of gold that day, which was only enough for one night, but now, I am afraid that it will be more than five or six days.

"It's really stingy!" Yang Xuan said helplessly: "There will be a period later!"

After finishing speaking, he had already looked at Zhang Heng who walked in.

Zhang Heng hugged his fists at Yang Xuan and said, "Young Master Ren, please explain the method." ”

He didn't specify Yang Xuan's identity, it didn't matter, what he needed, or what the Qingxue royal family needed, was just that method.

Zhang Heng took the pen and paper, and Yang Xuan was not polite, he directly took it and drew a circle on the white paper, and then drew the diameter of the circle.

His drawing ability is really not complimentary, not only is the circle not like a circle, but even the diameter is crooked.

Zhang Heng frowned, grabbed the pen and paper and drew a circle again, as if he was drawn with a compass, and the straight line was also drawn with a ruler.

Yang Xuan didn't show any shame on his face, and explained directly on the circle drawn by Zhang Heng, making a cameo appearance as a primary school teacher.

That's why I call this fixed number pi. The explanation was completed, and Yang Xuan made the finishing touch.

Zhang Heng didn't answer, he was thinking quietly, and after a while, he suddenly got up, bowed respectfully to Yang Xuan, and said, "Mr. Dacai, please accept the old man's worship." ”

Yang Xuan hurriedly helped Zhang Heng up, he blushed a little, he really deserved this worship.

Zhang Heng got up and looked at Yang Xuan, and sighed: "I didn't expect that Mr. would study mathematics so deeply, compared with Mr., I am really like a frog at the bottom of a well, and I don't know if it's ridiculous." ”

Yang Xuan explained: "I'm just standing on the shoulders of my predecessors, and it's not worth mentioning. ”

He explained it in disguise, but Zhang Heng only regarded him as modest, and at this moment Yang Xuan's status in his heart reached a peak.

Zhang Heng looked at Yang Xuan again, and said a little embarrassed: "It stands to reason that I should have left at this time, but I have a doubt in my heart, I have been confused for many years, and I want to ask Mr. to answer it for me, I don't know what Mr. thinks?"

Yang Xuan nodded, anyway, he has nothing to do now, and there is nothing to lose by being a math teacher for Zhang Heng.

Zhang Heng looked extremely happy, he respectfully bowed to Yang Xuan as a disciple, and then said, "I wonder if Mr. has studied the shape of the triangle?"

Yang Xuan was stunned for a moment, is this to discuss trigonometric functions? It's not that he can't, but he's just afraid to say it, Zhang Heng can't understand it.

"There's some research!"

Zhang Heng said happily: "That's great, I have a question, it's like this, suppose there is a triangular shape object, the two sides are straight to each other, one side is oblique, I know the length of any two sides, how to know the length of the third side?"

Yang Xuan breathed a sigh of relief, isn't this the Pythagorean theorem?

However, when he really explained it to Zhang Heng, it took a lot of effort, because he had to transform the formula of the Pythagorean theorem into the mathematical knowledge of this world, which invisibly increased the difficulty of explaining.

It is impossible for him to tell Zhang Heng directly: A square plus B square equals C square, in that case, he will have to be an English teacher, and even, he will explain to Zhang Heng what is square and what is a root number.

After some words, Zhang Heng finally understood.

At this time, he was already shocked by Yang Xuan.

"Master is above, please be worshiped by the disciple!" As he spoke, he was about to kneel on the ground and kowtow to Yang Xuan.

"Hey, what are you doing, get up, it's dirty...... Oh, why don't you listen?"

finally pulled Zhang Heng up, Zhang Heng's attitude towards him was like seeing his own father.

"Mr. has the grace of teaching to his disciples, this worship, heaven and earth together. Zhang Heng said respectfully.

Thinking about it, what Yang Xuan taught him, although in the previous life on the earth, it was only the knowledge of elementary school or junior high school, but the formation of these knowledge, that one is not the condensation of the hard work of the predecessors.

In fact, in Yang Xuan's previous life, the more popular the knowledge, the more classic it is, and if it is passed on in this world one by one, it will definitely be a shock.

Not to mention anything else, take the multiplication formula of the second grade of primary school learning, if Yang Xuan teaches it, it will definitely cause a great change in the world's science and engineering, and at that time, Yang Xuan will be regarded as the existence of a Taoist ancestor and admired by the world.

After Zhang Heng left with a thousand thanks, Yang Xuan had the time to study this storage ring that he almost sold himself in exchange.

Swept away, he was already overjoyed.

Although the space inside this storage ring was not large, only about the size of a bedroom, when Yang Xuan's divine thoughts scanned, the strange fluctuations coming out of the ring attracted his attention.

Why does the ring have its own space? This is the question he is thinking about now.

This kind of fluctuation, can he simulate it with aura, and if so, does it mean that he can carve out his own space without relying on the storage ring.

Thinking of this, he was also a little excited.

However, after careful study, he always felt that something was missing, which interrupted his train of thought for a while.

He had a lot of fun with the things he had in his arms and then watched them appear in his hands, and this strange feeling was really wonderful.

The next day, he went straight to the counter to return the room.

Of course, he settled the arrears very happily, so as not to let Qingshuang see jokes for this.

After leaving the inn and walking around the city, he returned to his original form.

Back at Meng Qingqing's house, he first went to refine some Huitian Pills, then after thinking about it, he refined some more Weight Loss Pills.

After another period of time here, Meng Qingqing came again.

"Are you injured?" Yang Xuan's face sank when he saw Meng Qingqing for the first time.

。 m.