I

It's evening again.

After school, Fei Chun was sent to the cafeteria to wait for food, while Pang Chunlai went to the hut to have a stomachache.

Fei Yuanjian stayed in the classroom stupidly, fidgeting as if he had ADHD. He didn't want to make up classes every day, but except for Zhao Han, the other classmates didn't play with him, and even laughed at him when they saw it.

Is it so difficult to be a good student?

Fei Ruhe was in a similar situation. He was flipping through "Algorithm of the Tongzong" in his hand, and his thoughts were already drifting to the sky. Hell, arithmetic is more difficult than the Four Books.

Finally, Fei Ruhe couldn't help but said: "Sir, he took a dump and hasn't returned for a long time. He must have a stomachache. I don't think there is any need to learn arithmetic today."

"Yes, yes, no need to study anymore." Fei Yuanjian quickly agreed. He came here to make friends, not to study hard together. Based on his basic knowledge, if he really wants to make progress, he must first go back to the Mongolian School to re-read children's books.

Xu Ying didn't dare to speak. Although she was no longer so scared, she still had a barrier with the rich young master.

Zhao Han smiled and said: "Then you go to practice martial arts in the bamboo forest."

Fei Ruhe, who had already stood up, sat down again after hearing this and said with a smile: "If you don't want to go, then I'd better stay."

Fei Ruhe also had a guilty conscience, and he had a hand in posting the big-character posters, so he didn't dare to be alone with Fei Yuanjian.

"Haha, then I'll stay and study too." Fei Yuanjian echoed with a silly smile. He had nowhere to go. He had offended too many classmates in the past, and he was easily beaten by a group of people once he was left alone.

Fei Chun ran back and forth several times and finally brought everyone's meals.

Not long after, Pang Chunlai returned to the classroom, picked up his chopsticks and said, "Learn while eating. This arithmetic is more practical than studying Confucian classics. From now on, whether you are local officials, marching and fighting, or managing family businesses, Arithmetic is definitely useful."

"Yes." Fei Ruhe, Fei Yuanjian and Fei Chun all looked sad.

Xu Ying sat upright and eagerly waited to learn new knowledge.

As for Zhao Han, he remained silent throughout the whole process, immersed in familiarizing himself with various related terminology in ancient times.

For example, "long" and "wide" are often called "wide" and "conong". If you don’t understand this, it’s useless no matter how good you are at math, you won’t even be able to understand the questions.

Another example is the unit of time, hour, quarter, hour, and point.

There are 12 hours in a day and 2 hours in an hour. Everyone knows this.

But there is some trouble in keeping track of time. In the past, it was 100 quarters a day, and Western clocks were introduced, but it was changed to 96 quarters a day. I heard that in Beijing, someone suggested changing it to 108 seconds, but it’s a mess anyway.

In addition, there are also very common time units such as seconds, awns, and suddens.

Moreover, Zhao Han was surprised to find that "Zhou" actually existed in ancient China, and it has been used for two thousand years.

There are 7 days in the ordinary week and 8 days in the leap week. During the Qin and Han Dynasties, they were used to determine working days. Imperial officials only worked 6 days a week. Just because of the trouble of converting between normal and leap years, I didn’t use it much later. It is more intuitive and convenient to use it on the thirtieth day of each month.

The word "week" also exists, specifically referring to the seventh day of July, and is derived from the wedding date.

The week is approaching, and the wedding day is approaching.

Zhao Han was already familiar with arithmetic, but then he was reluctant to learn it and pestered Pang Chun to explain various units and terminology.

⊥〣＝‖_×

Can you see what the above means?

The arithmetic version of 6322.14 (the decimal must be half a square shorter).

In fact, as long as you get used to it, they are no different from Arabic numerals, they are just different symbolic expressions.

…

Seeing that Zhao Han only focused on professional terminology and did not like to learn basic arithmetic, Pang Chunlai smiled and asked a question: "Zhao Han, can you calculate it?"

It is true that Zhao Han is progressing too fast and is obviously tired of studying. He needs to deal with difficult problems in his debut!

Xu Ying, Fei Ruhe, Fei Yuanjian and Fei Chun read the questions curiously, and then were collectively dumbfounded.

The content of the title is roughly: "Only 280,000 shi of military rations are left on the front line, and 7,000 shi are consumed every day. If we transport food supplies, we can reach it in 25 days, and consume 1,000 shi per day on the way. Please tell us how much food needs to be transported to allow the frontline soldiers to last for 90 days. ?”

Xu Ying thought carefully about how to solve the problem, and her mind was in a state of confusion. He had just started learning multiplication.

Fei Ruhe couldn't help but said: "Sir, aren't you making things difficult for me?"

"I didn't ask you to solve the problem," Pang Chunlai looked at Zhao Han with a smile, "If you can't solve it, just practice hard from now on!"

Zhao Han did not answer the question immediately, but asked: "After the food transport team completes the military order, should they stay on the battlefield and wait for ninety days, or should they immediately return the same way? In other words, after transporting the military food, they will not care about the life or death of the food transport team. Mr. The question is vague and has three different answers.”

Pang Chunlai laughed loudly: "It's rare to have a thoughtful mind. Please figure out all three solutions."

Zhao Han picked up the straw paper, assumed that the number of grains transported was X, and then started to make equations.

A linear equation of one variable is just an elementary school question.

Three answers came quickly.

All the students were immediately shocked. Whether they were good students or bad students, they all looked at Zhao Han with admiration.

Pang Chunlai snatched Zhao Han's calculation script. The strings of mysterious codes made him dizzy. Modern equations were a sacred book to him.

"Which country's characters are these?" Pang Chunlai asked confused.

Zhao Han tentatively asked: "Sir, do you know Xu Guangqi?"

Pang Chunlai nodded and said: "Although I have never seen Xu Guangqi as my teacher, and I don't even know his name, I have heard of his name for a long time. After the defeat of Saarhu, he was ordered to organize and train a new army in Tongzhou. Now that the new emperor has ascended the throne, According to the Chaotingtang newspaper, he has been reinstated as an envoy to the Qing army."

Qing army means checking the status of the army, including general officers, troop quotas, training, food and pay, ordnance, etc.

Xu Guangqi's current duty is to clean up the Ming army.

Since Pang Chunlai has never seen it, Zhao Han can just talk nonsense.

Zhao Han opened his mouth without blinking: "There was a missionary from the West named Matteo Ricci who came to the Ming Dynasty with "Elements of Geometry". Xu Guangqi translated this book, and my father had the honor to read it during his lifetime. These numbers are all from Western legends." Come."

"Tell me about it." Pang Chunlai was immediately interested. He asked the children to eat and do problems while he asked for advice on Western arithmetic.

Zhao Han wrote out Arabic numerals and various arithmetic symbols, and marked Chinese characters below them one by one.

Pang Chunlai had no fondness for Arabic numerals, but was surprised by the convenience of Western arithmetic symbols. However, if you want to introduce those arithmetic symbols, you have to use Arabic numerals.

The calculation expression is not possible, because the "4" in calculation looks exactly like the multiplication sign, and the "2" looks almost like the equal sign.

Pang Chunlai could only forcefully compare the two characters, and then look at Zhao Han's equation.

"This is Tianyuan Technique!" Pang Chunlai slammed the table.

Xu Ying and San Fei, holding chopsticks in their hands, looked over stupidly. They had no idea what it meant.

Tianyuan Technique is the equation.

Pang Chunlai added: "This is Taixi's Tianyuan Technique. It only lists one element. Can you explain two, three, and four elements?"

Zhao Han asked curiously: "Sir, can you use arithmetic to solve the four yuan problem?"

Pang Chunlai shook his head and said: "Some people know it, but I don't. It is said that Zhu Shijie, a master of arithmetic in the Yuan Dynasty, once created the four-element solution. But I have only read his "Arithmetic Enlightenment" and have not had the opportunity to see his "Four-Element Jade Mirror" "A book. Without saying so much, I will give you a question and you can use Taixi's Tianyuan Technique to solve it."

Soon, a question came out.

Zhao Han solved the problem using a linear equation of two variables and handed over the solution draft: "Sir, please take a look."

Pang Chunlai was not familiar with Arabic numerals, so he could only compare them and check them slowly, then clapped his hands and praised: "Wonderful, wonderful!"

Using arithmetic to solve linear equations of two variables is actually very fast, and the efficiency is not inferior to linear equations.

However, the problem-solving process of calculating Tianyuan Technique is more complicated to express on paper and is far less simple than an equation.

If it is a two-dimensional quadratic question, then Yuan Shu will be even more complicated!

Pang Chunlai laughed loudly: "This technique is so ingenious that I come to teach it as a teacher."

Students teach teachers?

Xu Ying and Sanfei were even more stunned, feeling that Zhao Han was really powerful!

Pang Chunlai said to the four of them: "You should also learn together."

Since then, their arithmetic learning speed has doubled compared to before, and even Fei Yuanjian found it easier.

After all, they are not fools.

The relationship between Fei Yuanjian and everyone has always been very delicate.

Like sticky candy, we read, practice martial arts, and learn arithmetic together every day. Xu Ying accepted him quickly, but others had doubts in their hearts, and Ruoji Ruoli always had reservations.

The winter solstice arrives in a blink of an eye.

The Martyrs' Archway has been repaired, but the approval from the court has not yet come out.

This thing needs to be approved by the government at all levels, and then it can be bestowed in the name of the emperor.

But by the end of the Ming Dynasty, basically just give money.

The slow one goes to the county magistrate, the fast one goes to the censor. After it was sent to the court, the emperor didn't care at all. The cabinet directly handed it over to the Ministry of Rites, and the officials of the Ministry of Rites could approve it with money.

The Chastity Arch is also exclusive to the rich!

Because the imperial court only allocated thirty taels, which was not enough to erect an archway, more money was needed for up and down management. People with no money and status, unless local officials are motivated by political achievements, will not be able to erect a memorial arch no matter how loyal they are.

Etiquette cannibalism?

Sorry, if your family has no money, you are not even qualified to be eaten.

(Please give me a monthly ticket, a recommended ticket. Friends who read books on the Internet, this book was first published on the Qidian Chinese website, you can download the "Qidian APP" and come and have sex together.)