Analytic geometry was founded and developed by two great men - Fermat and Dicar.

Fermat is a generalist who has had a profound impact on modern times in philosophy, physics, physiology, mathematics, theology, etc., but among all his achievements, the least mentioned is analytic geometry.

"Analytic geometry, in the history of mathematics, is equivalent to the role of the steam engine in the industrial revolution. ”

Modern mathematics can be said to be variable mathematics in essence, and the first milestone of variable mathematics is the invention of analytic geometry, which has epoch-making significance in the history of mathematics, and is a monument to the revitalization of European algebra since the Renaissance.

"The great development of modern mathematics in the past life should be attributed to analytic geometry to a large extent. ”

Although the analytic geometry of the Qin Dynasty could be figured out by itself, the Qin Dynasty did not want to do everything himself, and all the subject knowledge was written by the Qin Dynasty.

It is better to teach a man to fish than to teach him to fish.

After the Qin Dynasty left, the whole of China would not fall into the vicious circle of invention, disappearance, re-invention, and disappearance, and science and technology would always stand still.

The Qin Dynasty looked at it repeatedly.

"Huh?" Everyone looked at the Qin Dynasty, only to see that the booklet with all kinds of incomprehensible symbols, formulas, and graphics was actually flipped over by the Qin Dynasty.

Every time he looked at a page, he looked at it. ”

Mathematical geometry is often a complex problem that does not take up much space, but to understand it, you must think carefully and organize it slowly to sort out the order.

In the past, when Zhang Jiucai took this geometric number solution and asked the ancestors of the martial arts academy for advice, those people were often confused at first glance, and asked Zhang Jiucai to explain it on the side, but in this way, they all frowned and couldn't say too much to convince Zhang Jiucai.

Everyone looked at each other. At this time-

"Good. ”

Qin Chao put down the booklet and looked at Zhang Jiucai, "First of all, you chose the right direction, Brother Jiucai, you were extremely talented in mathematics back then, and now that I have read your geometric number solution, I find that I underestimated your talent in the past." ”

The Qin Dynasty was full of praise.

Zhang Jiucai's face turned red suddenly, and the whole surroundings were quiet.

"How?"

Qin Chao was stunned for a moment, and found that everyone's expressions seemed to be a little wrong, but Qin Chao didn't expect that it was he who saw it too quickly and made everyone misunderstand, after all, Qin Dynasty's mathematics has always been the best among everyone, and the answer to a difficult problem can often be seen at a glance.

"You are ......" Qin Chao was about to comment more on this geometric number solution.

"Brother Haifeng. Zhang Jiucai's voice seemed to come out of the ground, and he stared at Qin Chao with a swollen face.

"Have you really read it and understood?" Zhang Jiucai said in a deep voice.

"How?"

The Qin Dynasty was immersed in the excitement of the birth of analytic geometry, in fact, in the manuscripts of the Qin Dynasty in recent years, this kind of analytic geometry is everywhere, but the manuscripts of the Qin Dynasty are full of sweat, and it is impossible for everyone to look at them, the important thing is that there are not only analytic geometry in this manuscript, but also more advanced mathematical formulas, etc., in order to cultivate the Tai Chi team, the Qin Dynasty ordered that once the Qin Dynasty sorted out, these manuscripts will be blocked and preserved by people, and no one is allowed to peek at them.

"I have a question here, and I ask Brother Haifeng to answer it for me first. Zhang Jiucai hoarsely dragged a piece of paper from the side and pushed it in front of Qin Chao, "Please take a look." ”

Qin Chaoyi frowned, took the paper, and swept his eyes to find that this was an analytic geometry problem.

"If you really understand the geometric solution I handed over, then you can still give the answer to this question, otherwise, you won't be able to understand it. Zhang Jiucai glared at the Qin Dynasty.

The answer is 8,73. Qin Chao replied with only one glance.

“8，73？”

Zhang Jiucai's eyes widened violently, this analytic geometry problem he Zhang Jiucai had to calculate it for a while, Qin Chao gave the answer at a glance It is nothing, but to give the answer, it is necessary.

"So...... He really ......" Zhang Jiucai's heart was pounding, and he looked at the Qin Dynasty incredulously.

In fact, although analytic geometry is not difficult for modern people, it is not difficult to learn it, and Descartes's "Geometry" was too difficult to understand that greatly affected the spread of analytic geometry, and it is for this reason that later generations wrote a lot of annotations for this, just to make it easy to understand.

Analytic geometry needs a lot of time to really understand, every concept, every formula, definition, etc., this is not a novel, no matter how smart you are, even if your IQ is twice as high as that of the current Qin Dynasty, it is impossible to understand it at a glance, at least a little time to think about it in your head.

"How could he see it so quickly? unless one could...... Before I studied this geometric solution, he had already studied it in a similar way, even more thoroughly than I did, so he could understand my research at a glance. ”

Zhang Jiu thought of this and felt more and more that this idea was right.

"This geometric solution, didn't you before?" Zhang Jiucai asked.

"Brother Jiucai. Qin Chao lowered his eyelids and said with a smile, "Don't ask me if I have studied or have the same results, in this world, it is not only Lao Tzu who says 'Tao is Taoist, very Tao', and it is not only Confucius who says 'Do not do to others what you do not want to be done to yourself'." ”

Zhang Jiucai retracted his gaze and pondered slightly: "I understand." ”

"Brothers. Qin Dynasty looked around again, "Zhuge Kongming has the talent of the heavens and latitudes, he has worked hard all his life, and he has done his best, why can't he keep the queen? "Brother Haifeng is polite!" "Brother Haifeng don't worry!" everyone shouted repeatedly, and many people were thoughtful.

"Brother Jiucai. Qin Chao moved his gaze back to the booklet in his hand, "You asked me before, would it be too much to study geometry like this, or would you take the wrong path." Qin Chao's eyes lit up, "Although everyone can't say why, I can tell you with certainty that you are on the right path, and you can't be right." Qin Chao's voice exuded an unmistakable firmness.

Qin Dynasty understood that Zhang Jiucai, the reason why it was difficult for the entire Martial Arts Academy to explain this analytic geometry was because they were not clear about the need for analytic geometry, and they were ignorant in many places, and they always felt that mathematics could be figured out when needed. What they think is not a big mistake, but then the efficiency will be higher and then lower, and there will be many obstacles when entering the deep waters of science.

This also caused that ancient China had science and technology but little science.

In fact, analytic geometry played a very important role in the in-depth development of science.

Zhang Jiucai's face was excited, using mathematics to study geometry, although he always felt that it was of a certain significance in his heart, but the senior brothers and seniors who asked, no one was very sure, and the Qin Dynasty was the first extremely affirmative, Zhang Jiucai was still more convinced of the Qin Dynasty, not to mention, Zhang Jiucai had confirmed in his heart that the Qin Dynasty had already studied in this direction, and it was studied deeply.

"Brother Haifeng, can you elaborate?" Zhang Jiucai looked at the Qin Dynasty expectantly.

Qin Chao smiled slightly, knowing that although Zhang Jiucai was smart, after all, he was young and had little experience, so it was naturally impossible for him to be as convinced of the meaning and role of analytic geometry as Dikar and Fermat.

"Your geometric number solves the combination of guò shape and number, making mathematics a double-sided tool......" Qin Dynasty's understanding of analytic geometry came from years of study in junior high school, high school, and college in his previous life.

"Geometric concepts can be expressed algebraically ......"

"On the other hand, it can give a geometric explanation to the algebraic language......

In the middle of the room, Qin Chao talked eloquently.

Zhang Jiucai's eyes became brighter and brighter.

Standing on the explanation of the civilization of later generations, the Qin Dynasty made his words in this regard different from others, and every sentence could be pointed to the truth, which naturally made Zhang Jiu in the fog have a feeling of pulling out the clouds and seeing the fog.

Soon, the Qin Dynasty explained the meaning, role, benefits and other aspects thoroughly.

"In short, the significance of this kind of geometry is very great, Jiucai, I can only give you directions and encouragement in this regard, and the rest is up to you. Qin Chao said in a deep voice, "By the way, you name this kind of geometry geometry as geometric number solution, I have an idea for this name, it is better to change it to analytic geometry." ”

"Analytic geometry?"

Zhang Jiucai groaned slightly, and then laughed: "This name is good, by the way, I still have some specific questions in this analytic geometry." ”

"Please!"

Then the Qin Dynasty answered the specific questions in the booklet, and at the same time-

"Brother Jiucai, I built this thing and named it 'coordinates', and this coordinate should be drawn like this, Wuji gives birth to Taiji, the way of the world, there are positive and negative, so I build yì ......"

"Coordinates, that's not bad......"

"Brother Jiucai, don't use Chinese characters for the name of this axis, it's too complicated, let's use a simple ......"

"Just do what Brother Haifeng said......"

......

The Qin Dynasty also gave advice from time to time to get Zhang Jiucai's analytic geometry back on track.

Soon Zhang Jiucai left excitedly.

"Zhang Jiu was able to independently create analytic geometry, although the content is still very superficial, but at least it shows that my cultivation is effective. Qin Chao nodded in his heart and looked at the young man next to him.

"Brother Helian next, what do you want to ask?"

......

One by one, they stepped forward to ask the Qin Dynasty for advice, and everyone's outlines, copywriting, and essays were ...... Generally speaking, the content of various brochures is almost all seen at a glance in the Qin Dynasty, and it can be understood in general, even if it is not understood slightly, everyone can understand it as long as they explain it a little, after all, in addition to the ancient texts, the knowledge of other aspects of the Qin Dynasty is far above everyone.

(Thank you for the tip from the 'dog bite' tip!)