After Zhuge Liang finished writing his reply, he went to the back room and handed his eldest brother's first volume of family letters to his eldest sister Zhuge Yun and second sister Zhuge Yu, who had just finished washing dishes and clothes.
Zhuge Yun is already nineteen years old. If he hadn't been homeless and unable to settle down, he would have been considered an older leftover before he got married at this age.
Zhuge Yu is seventeen years old, and the pressure is not much less.
A few months ago, they also secretly observed Kuai Qi, Pang Shanmin and others who came to visit.
But Kuai Qi is really a loser. He is just a noble family. Who made the Kuai family now the number one civil servant family in Jingzhou? Zhuge Yun was very dissatisfied with the other party, but he also had a faint consciousness of self-sacrifice in his heart.
As for Pang Shanmin, his knowledge and character are better than Kuai Qi. After all, he is Pang Tong's cousin. But the appearance became more and more clumsy and unsightly. After all, Zhuge Yu has his eldest sister to protect him. Sometimes he wonders: If his eldest sister sacrifices himself, will he not have to sacrifice anymore... The Kuai family is enough to cover the Zhuge family, right?
Therefore, just before dinner, they heard the third brother quietly playing treasure and saying: The eldest brother suddenly became prosperous in Guangling. General Zhendong treated him as a disciple and brought him countless belongings. The melancholy Zhuge Yun and Zhuge Yu were instantly relieved.
"Suddenly, the eldest brother is so powerful? Then we don't have to depend on others or rely on marriage to gain status?" The two sisters' first reaction was the same. They imagined that if the eldest brother's situation could be better than that of his uncle, then they would decisively join him. !
Even if you want to get married in the future, you should marry someone rich and handsome, and you don't have to sacrifice your character and appearance for money, power and status.
Now that their second brother had finally read the letter home and written a reply, they eagerly gathered together to read it together.
Zhuge Jin's confident writing also made them feel strange.
"My eldest brother used to be humble even when writing family letters, but now he is as domineering as Master Meng. He has changed so much, it shows that he has really prospered." Zhuge Yun, who is the closest to Zhuge Jin and knows him best, couldn't help but praise.
Zhuge Yu looked at it for a while, then pushed his second brother: "Ah Liang! If the eldest brother can really protect us, the eldest sister and I will go and seek refuge first. You can stay in Jingzhou and mediate with the Huang family's wife.
Anyway, you men, just think of marrying a virtuous wife. If you are not satisfied with the beauty, you will still have the opportunity to take concubines and have sex in the future. We only have one chance, so I won't keep you company. "
Zhuge Yu had also met Huang Yueying and knew that his second brother and the other man were quite friendly - of course, just as ordinary friends.
The young lady has good character and knowledge, but she is not fair and beautiful, and her hair is not black and shiny. At first glance, she seems to be deficient in qi and blood and lack of qi.
Zhuge Yu felt that compared to what she had experienced with her eldest sister, the second brother's situation was acceptable. After all, they had similar interests, and it would not be too late to find beautiful women to take concubines in the future.
Zhuge Liang originally wanted to analyze his eldest brother's changes with his eldest sister and second sister, but Zhuge Yu made him anxious. He left the letter and left, going back to the house to figure out the secret book given by his eldest brother.
…
After all, Zhuge Liang is only sixteen years old, and boys are often not as mature as girls of the same age, so the second sister teases him about his relationship with Huang Yueying, which makes him lose face.
At this time, answering questions is the best way to divert attention! He opened his elder brother's second scroll and began to study it.
"I want to see what progress my eldest brother has made in the past two years. He actually thinks he can teach me. Isn't he looking for some obscure knowledge..."
Zhuge Liang scanned it quickly and found that the first half of the second volume was mainly a table of contents. He summarized and made an index of the contents of the subsequent dozen volumes.
The second half is an exhortation to study, mainly talking about the nature of studying and other major principles.
Zhuge Liang pouted, what he needs now is a challenge! It’s about answering questions to relieve the embarrassment! I don’t want to read the same old stories just yet!
As for learning methods, can your elder brother’s learning methods be better than mine? If he had this ability, he wouldn't have been crushed by him back then.
So Zhuge Liang dropped the second volume and skipped it. He just clicked on the table of contents and jumped to open all the fifth to eighth volumes.
The catalog says that these four volumes are all about arithmetic! It is something more profound and comprehensive than "Zhou Bi" and "Nine Chapters".
Zhuge Liang knew very well that when he left his hometown two years ago, his arithmetic skills were definitely inferior to those of his elder brother.
Then let's first take a look at how much these things that the elder brother regards as good things weigh.
…
"Huh? What the hell is this?"
Not to mention, as soon as he opened the fifth volume, Zhuge Liang was really shocked by the head start.
Because he didn't recognize any of the ghost-drawing talismans in the scroll.
Fortunately, his desire to explore was very stable. He took a deep breath and looked at it carefully without fear or emotion. As expected, every symbol was explained before it was called.
"Ha! It turns out that it's just numbers and symbols from the Shendu Kingdom. The purpose is to omit the words 'hundreds of millions' and directly represent tens of millions with digits. It saves a lot of effort... This also makes it easier to use symbols to calculate directly. , which is much less labor-intensive than describing the algorithm in words.”
Zhuge Liang spent a cup of tea, first accepted the Arabic numerals 0 to 9, and then took a cup of tea to accept the "+-×÷/=" sign. He also brought a piece of wooden tablet and used a gray pen to connect the numbers. After writing it ten times, I realized how labor-saving this thing is.
After mastering the numbers and symbols, Zhuge Liang quickly regained his confidence when he looked at the first few questions listed by his elder brother for him to adapt to.
"Isn't this just a restatement of the Nine Chapters of Chicken and Rabbit in the Same Cage using body poison numbers and calculations? Why are there X and Y... Well, it seems that these two runes mean A, B, and C. In this question They represent the numbers of chickens and rabbits respectively..."
"This method expresses the calculation formula of hook, three strands, four strings and five using body poison. It is nothing new. However, this idea of using a symbol to substitute a symbol into the formula has simplified it a lot. You don't have to think about the meaning every time. You only need to follow the numbers. Dealing with..."
In just two questions, Zhuge Liang summarized the main benefits of using numbers and symbols, and a flame of "mathematical abstraction" was vaguely lit in his heart.
The traditional "Zhou Bi" and "Nine Chapters" are too application-oriented, and the general abstraction of mathematics is definitely not as good as that of later generations. Zhuge Jin just sorted it out and rephrased it, which brought about a new improvement in the second brother's way of thinking.
The ancients completed the study of "Zhou Bi", which was roughly equivalent to the fourth and fifth grade of elementary school in later generations. That is, the four arithmetic operations, fractions, negative numbers, and calculation of the perimeter and area of simple graphics.
After learning "Nine Chapters", you can roughly improve to the first grade mathematics of later generations, including the Pythagorean theorem and various multivariable linear equations. It just lacks circular geometry, square roots, and irrational numbers compared to later generations.
It took Zhuge Liang only half an hour to re-understand the mathematics from later generations to the first grade of junior high school. It was very easy.
"Brother underestimates my basic skills! However, he can also understand these things. It seems that he has made a lot of progress in the past two years." Zhuge Liang thought proudly.
He continued to read bravely and diligently. The second half of the fifth volume was about something called the "Circle Cutting Method" and the derivation of the area algorithm principles for other complex geometric figures.
Zhuge Jin wrote a very detailed process and gave the conclusion at the end. It was not like the proof process that lacked basic formulas like the textbooks of later generations and directly asked students to memorize it.
Such a simple and logical lesson plan would be difficult for others to write on their own unless they were gold medal lecturers themselves.
"Huh? That's interesting. Why didn't I expect that stretching a circle infinitely would result in countless triangles with the circumference as the total base length... and such odd-shaped patterns, the area can also be deduced after cut and repair conversion The algorithm will definitely be useful when measuring acres in the future, as you don’t have to go step by step for each row.”
Zhuge Liang's mood finally changed from the initial surprise to a slightly serious one.
This time it took him more than an hour to finally understand it.
After doing all this, when he recovered from his intoxication, he realized that the simple carving on the desk had already been finished.
The night at the beginning of the month was pitch black, and I didn’t know what time it was, maybe it was Xu time? Everything around was silent, and the sisters and third brother were already asleep.
Zhuge Liang still couldn't stop being excited and went to get the sixth volume again.
The beginning of this volume is the principle of the root sign, as well as trigonometric functions, and the irrational numbers derived from them - of course, Zhuge Jin used experimental methods to demonstrate, not purely mathematical methods.
I won’t go into details, but it is very step-by-step and very suitable for Zhuge Liang’s current knowledge structure.
Trigonometric functions and root squares follow the generalization of the integer solutions to the Pythagorean theorem in Volume 5 and are inspired step by step. The context is very clear.
By making up for these two shortcomings, Zhuge Liang was able to completely surpass the mathematical level of later first-year junior high school students, and he began to get a glimpse of the "trigonometric functions" of senior grades.
But this time Zhuge Liang finally suffered.
He looked at it for another half-quarter of an hour, still not knowing how to calculate it.
He really wanted to do an experiment. According to the method shown in the diagram by his elder brother, he could cut and make so many triangular wooden boards with specific angles, and then use a ruler to measure the length of the specific hypotenuse to get the function value and the root number.
But it was already dark, it was hard to make too much noise, and we couldn't find tools and materials, so we had to give up.
At this moment, Zhuge Liang was considered in the field of arithmetic and put away his contempt.
"Big brother must have had adventures in the past two years!" Looking at the completely incomprehensible content in the sixth volume, as well as the seventh and eighth volumes that were like heavenly books, he finally understood his position.
"The third and fourth volumes are about the basics of logical right and wrong and common sense in thinking. The ninth to eleventh volumes are about the common principles of heaven and earth. The twelve to fourteenth volumes are about the principles of life in farming and animal husbandry. The fifteenth and sixteenth volumes are about the experience of skillful application of craftsmanship...it actually covers It’s so broad. Did I underestimate what my elder brother had learned at the beginning? I shouldn’t have jumped to read it just now.”
After looking through the entire catalog, Zhuge Liang finally corrected his attitude and decided to take back his eldest brother's original "Encouragement to Learning" and read it carefully from the beginning. Perhaps that way we can get twice the result with half the effort and avoid haste making waste.
He reopened the second volume that he had abandoned, put on a pious and peaceful mood, and read it without a trace of arrogance.
Perhaps this is one of the rare times in Zhuge Liang's life when he put away his "observation of the roughness" and seriously "worked to be pure".
——
PS: Please vote for the new book issue, collect it, and follow up for updates.
Tomorrow will be the end of Zhuge Liang's first experience of reading. His subsequent growth will be all about "practicing on the matter". He will study while encountering problems again and again, interspersed with writing, so that the plot will not be slowed down.
Thank you all for your patience. Thank you.
