Chapter 15

Li Hao didn't expect someone to ask questions so soon.

Wu Lin could not help shaking his head when he heard the general's question of drinking horses: "this question is actually very simple, but it is difficult to understand."

"Why do you say that?" Du Tao doesn't quite understand. As a Chinese teacher, he only knows a little about these mathematical proper nouns.

"There are too many typical models for generals to drink horses. There are 16 common models. If someone deliberately wants to ask Li Hao, maybe let him analyze more than a dozen models." Wu Lin said his concern.

But unexpectedly, Li Hao just smiled and then said, "in fact, the problem of general drinking horses, that is, the shortest path problem, is mainly based on 'between two points, the shortest line segment', 'among all line segments from point to line, the shortest vertical line segment', and solved by using the properties of axisymmetry, plane expansion diagram and other knowledge."

"In particular, we should use axisymmetric transformation and transform spatial problems into plane problems to solve the shortest path problem in junior middle school mathematics."

"Then I'll draw some common models for you here. These questions have traps. Oh, classmate, do you want to take notes?"

While Li Hao picked up the chalk, he also looked at the male classmate who had just asked questions.

The boy was stunned, so he opened the notebook on the table and prepared to take notes.

Li Hao drew a simple model on the blackboard behind him, then turned around and said, "let me tell you, first, there are two cases in two points and one line. The first is that two points are on the opposite side of a straight line, points a and B are on both sides of straight line n, and find a point P on N to minimize PA + Pb."

"This type of question has been done many times. The basis is that the line segment between two points is the shortest. What kind of model is more difficult? That is the shortest path problem in the expansion diagram of three-dimensional graphics."

"Let's draw a cylinder first, where ABCD is its axial section, ab = 8 π, BC = 3. If an ant wants to crawl from point a to point C, what is the nearest distance?"

As soon as the problem came out, the students immediately began to discuss it.

Because in the cognition of junior middle school students, general drinking horses is generally a problem of plane points and lines, rarely involving three-dimensional graphics, and it is still a cylinder.

Seeing that no one seemed to be able to say the answer, long Jiayang immediately asked Ji Mingcheng: "Mingcheng, can you calculate it?"

"It's not difficult, but I can't turn my head for a moment." Ji Mingcheng frowned and painted on the paper.

Long Jiayang heard that even Xueba in the class was so difficult to do this problem. He was immediately happy: "Hey, even Xueba can't do it. It seems that few can do it here."

He even craned his neck and looked at Liu Xiuyuan at the front left. He found that she didn't write a complete answer on her draft paper, so he was more convinced that this was a difficult problem.

But only Miss Wu Lin laughed.

"What's the matter? It's hard?" Du Tao asked anxiously.

Wu Lin shook his head: "this boy is a thief. In fact, this problem is not difficult. It just converts the plane into a three-dimensional cylinder, which makes many students unable to start."

When Li Hao saw that no students answered, he said, "in fact, we only need to expand the side of the cylinder to find the shortest distance for ants to crawl. The result can be obtained by 'the shortest line segment between two points'."

"Expand the cylinder, connect a and C, ab = 12 · π · 8 π = 4, BC is equal to 3, AC is equal to the square of 4 under the root sign plus the square of 3, and the final result is equal to 5."

After Li Hao finally wrote the answer on the blackboard, he looked back at the boy: "do you understand this variant problem?"

The boy seemed to blush. He finally nodded and sat down.

In this way, in the next half hour, the students under the stage asked Li Hao five or six questions one after another. He could answer them like a stream, and even set aside some time to explain the extension problems to them.

His performance completely conquered the students below.

At the age of junior three, as long as you have level and talent, you will be respected and respected by many people.

"Pa Pa Pa!!"

The students even spontaneously applauded Li Hao.

In fact, not only the students, but also the teachers standing behind were surprised.

Li Hao's state today is like a teacher who has been engaged in education for many years. He is even more experienced than some teachers who have just come to the school.

Most importantly, the rhythm of his lecture was just right, so that Du Tao couldn't help sighing: "this boy, after reading, is a teacher."

"It is estimated that his ambition is not to be a teacher." teacher Wu Lin narrowed his eyes and said thoughtfully.

But just then, a girl stood up. Li Hao looked over and found that she was a student of class 8 again.

She said bluntly, "just now they were asking questions about mathematics, physics and chemistry. Can I ask you questions about liberal arts?"

Li Hao smiled bitterly in his heart: the head teacher of class 8 really doesn't give up. His soul doesn't disappear.

So he said, "well..."

"In fact, I'm just a student of 46 in grade. Not every subject is strong. Otherwise, I can get the first in grade, don't you think so."

As soon as this sentence came out, everyone agreed. After all, boys' liberal arts are generally weak, which is also a default fact.

"But I can do my best. Ask."

As soon as Li Hao's conversation turned, he met directly!

The girl seemed to be ready. She picked up the book and read, "who is the emperor with the least concubines in the unified dynasty?"

"Wow ~ ~"

When many students heard this question, they began to coax.

Because they all know that the emperor's harem has three thousand beauties.

If you ask the emperor with the fewest empresses, they really don't know.

But the students in class 16 gradually found something wrong.

"Hey, you say, why do the students of class 8 always ask these strange questions?"

"Yes, even the emperor with the least concubines asked. How could brother Hao know!"

"Yes, we don't take these tests in books!"

"Shit, beat them later."

Xu Zijun was very angry. In fact, he noticed something wrong as early as the third student in class 8 asked.

Isn't it obvious to bully your brother?

Long Jiayang also said, "brother Jun, you'll teach the two men and the woman later."

After hearing this, Xu Zijun turned and looked at long Jiayang.

Long Jiayang immediately changed his mouth and said, "I mean, I took the girls in our class to ask the girl for advice, advice..."

When Li Hao heard this question, he was happy, and then said, "in fact, the answer to this question has also appeared in history books."

"Ah? No?"

"True or false?"

"Brag."

Li Hao immediately wrote the three words Zhu Youzhu on the blackboard: "Zhu Youzhu of the Ming filial piety sect!"

"He is the only monogamous emperor in history. He has only one queen without concubines and beauties; Emperor Xiaozong and empress Zhang get along day and night, the same as ordinary people's families; moreover, he is also a good emperor, diligent in political affairs, attaches importance to justice, speaks openly, and tries to reverse the corruption of government!"

Everyone was stunned when this paragraph came out.

They think, why does Li Hao even know how many wives the emperor has?!