173.

At this moment, Cheng Li didn't know what the little arithmetic boy was doing, and after entering the second layer, he threw himself into the ocean of arithmetic.

"Today there is a third, and a fifth of them. How do you get it?"

Seeing the question in the middle of the second layer, the huge "zero, zero, zero, zero" light word hanging down, Cheng Li couldn't help but breathe a sigh of relief.

He didn't answer the question right away, but thought to himself.

"This is the seventh question in the "Nine Chapters of the Sutra", Volume 1 'Fang Tian'. It seems that the little arithmetic boy did not re-randomize the question bank. ”

Cheng Ligang is also very worried that his identity as a plane traverser will be exposed, so will he choose a new set of questions for this arithmetic tablet?

Because according to the rules of the arithmetic tablet, since there is a rule of not drawing the question bank of the plane, it means that the arithmetic tablet does not want the examiner to draw the questions he has seen.

So theoretically, since I know that this set of questions has been seen by myself, the arithmetic tablet should change a set of question banks.

"Forget it, it doesn't matter, if it's all about some of the topics I remember, that's fine. ”

And Cheng Li found a strange thing, on the hanging light curtain, at the bottom right of the biggest question text, there were some notes written in small characters.

Note: From the first volume of the Nine Chapters of the Sutra. ”

Cheng Li looked at it, and was a little speechless in his heart, is this the arithmetic monument giving up on itself?

"Forget it, whatever he does, it won't have much impact on me anyway. ”

Cheng Li didn't bother about this matter anymore, and then he learned the lesson of the last time, this time he calculated a little in his head first, instead of saying the answer directly on his back.

Because now that I have become a cultivator, my brain is getting better and better than before, and my memory is much better than before.

Therefore, Cheng Li was careless just now, and directly said the answer to the first layer of questions on his back. Because of this, Xiao Shutong saw the clues, thus exposing his identity as a traverser.

"Eleven out of fifteen. ”

This question is very simple, Cheng Li just calculated a little, and said the answer without thinking.

Soon, Cheng Li passed the second layer.

The next third layer, the fourth layer, and all the way to the twentieth layer are the contents of the Nine Chapters of the Sutra.

It's just that it's getting harder and harder later on.

For example, the eighteenth layer is already the content of the eighth volume of the "Equations" volume of the Nine Chapters of Arithmetic.

"Today there are three Bing on He, two Bing in He, one Bing in Xia He, 39 buckets in the real He, 2 Bing in the middle He, 1 Bing in the lower He, 34 buckets in the real He, 1 Bing in the middle He, 2 Bing in the middle He, 3 Bing in the lower He, 26 buckets in the real 26 buckets. Q: Upper, middle, and lower Heshi are all geometrical?

Cheng Li thought for a moment.

This question already involves algebra knowledge, and is the first question in the eighth volume of the nine chapters of arithmetic, "Equations".

In fact, in the vernacular, it is a system of ternary equations.

3x+2y+z=39

2x+3y+z=34

X+2y+3z=26。

After translating that passage into Chinese, one can list such a system of ternary equations.

So basically, as long as you have a good study of junior high school mathematics, you can solve the answer.

So Cheng Li barely had much effort, and it was easy to calculate the answer and replied.

"Answer: Shanghe Yibing, nine buckets, one of the four buckets, one of the four buckets, one of the four buckets, one of the four buckets, one of the lower He, two buckets, three of the four buckets. ”

"Correct. ”

When the light characters drop these two large characters, a passage to the 19th floor emerges.

Then on the 19th floor, the positive and negative arithmetic of the "Nine Chapters of Arithmetic" appeared.

This is also an important contribution made by the Nine Chapters of Arithmetic in the history of mathematics in the ancient world, that is, for the first time, the concept of positive and negative numbers was explicitly proposed, more than a thousand years earlier than Western mathematics.

Therefore, when answering the question on the 19th floor of the arithmetic tablet, Cheng Li specially explained the original solution idea of the third question in the eighth volume of "Nine Chapters of Arithmetic".

"The technique says: such as the equation, each is taken from the place, and the positive and negative techniques are entered. ”

"Positive and negative techniques say: the same name is divided, different names are beneficial, positive and negative are not negative, and negative is not positive. Its different names are divided by each other, the same name is beneficial, the positive is not into the positive, and the negative is not into the negative. ”

After Cheng Li answered, the word "correct" fell again, and then Cheng Li stepped up to the 20th floor.

"And there are three hundred seventy seven thousand two hundred seventy five thousand six hundred twenty-five steps. Q: Square geometry?

This is actually a problem of prescription art, from the fourth volume of the "Nine Chapters of Arithmetic", "Shaoguang" volume.

Translated into the vernacular, it is: what is the length of a square with an area of 3,972,15625?

Cheng Li also gave the answer easily.

He replied, "Sixty-three thousand twenty-five steps." ”

"The prescription is said: the accumulation is real. Borrow a step, super first-class ......"

After getting Cheng Li's answer, the light word also dropped the "correct" answer.

When stepping on the 20th floor, Cheng Li also had some emotions in his heart.

"The nine-chapter arithmetic is undoubtedly a treasure in the history of ancient mathematics in our country, and there were early concepts such as negative numbers, fractions, square arts, and irrational numbers. ”

After entering the 21st floor, he found that the topic this time was not from "Nine Chapters of Arithmetic".

Rather, it comes from the "Zhou Ji Sutra".

"If you seek the evil solstice, take the sun as the hook, the sun as the stock, and the Pythagorean multiply each other, and open the way to get rid of it, and get the evil solstice. Q: If the hook is three strands and four, the chord geometry?

Cheng Li is naturally no stranger to this topic.

The Pythagorean Theorem should be the first mathematical work in the world to put forward the Pythagorean theorem, and it is also the earliest work that can be verified in China.

Therefore, after a little calculation in his heart, Cheng Li replied without thinking.

"If you hook three strands and four, then the string is five. ”

"Correct. ”

Cheng Li stepped on the next floor again.

Next, Cheng Li found that the problems began to be varied.

Most of them come from the ten books of arithmetic: "Zhou Ji Sutra", "Nine Chapters of Arithmetic", "Island Sutra", "Zhangqiu Jian Sutra", "Xiahouyang Sutra", "Five Classics Arithmetic", "Ancient Sutra", "Fixation", "Five Cao Sutras", "Sun Tzu Sutras".

In addition, there are some other works, such as some of Liu Hui's works, such as circumcision, yang horsemanship, island arithmetic and other related issues.

There are even some lost writings.

For example, Zu Chongzhi's "Embellishment".

If it weren't for the fact that there would be some small notes in the lower right corner of the current question, Cheng Li wouldn't know that these titles he hadn't seen were actually from "Fixation".

However, although I haven't seen the questions, the content is still what Cheng Li has learned, so Cheng Li easily answered the questions.

In this way, I walked all the way up in this arithmetic monument, climbing layer after layer.

Cheng Li has the illusion that he is always feeling that he is experiencing the rise and fall of ancient Chinese mathematics along the way.

However, the content of ancient Chinese mathematical calculations came to an abrupt end after the 100th floor.

The last ten questions from the 90th to the 100th layer are some of the works of Song and Yuan mathematics.

For example, the "Great Yan Total Counting Technique" mentioned in the "Nine Chapters of the Book of Numbers", and the interpolation method and stacking technique mentioned in the "Four Yuan Jade Jian".

There are even the most iconic "Tianyuan Techniques" and "Quaternary Techniques" in the history of the development of mathematics in the Song and Yuan dynasties.

This is an important attempt to symbolize algebra in the history of ancient Chinese mathematics.

The method of using the Tianyuan equation is very similar to the method of column equations in modern algebra.

After the end of the Yuan Dynasty, the development of traditional Chinese mathematics almost stagnated, and the entire Ming and Qing dynasties had no development in mathematics, and even kept regressing.

This period was the embryonic and rapid development stage of modern mathematics in the West.

The reasons for the alternation of the development of Eastern and Western civilizations and the decline of Eastern civilization in the history of the development of the modern world can be seen from the development of mathematics.

Therefore, when Cheng Li stepped into the 101st floor, he found that the questions were no longer the topics of some ancient Chinese mathematics calculations, but the Western modern mathematics that he was more familiar with.

A deep sadness appeared in Cheng Li's heart.

This means that even the arithmetic tablet believes that after the end of the Yuan Dynasty, there were no arithmetic topics worth entering in ancient Chinese mathematics.