Gu Xu looked proud: "Teacher Zhang said that I understand, what else do you say!" ”

Wang Xianchao clenched his fists, Zhang Xiaoli said this, he knew very well in his heart that he had lost.

However, even if you lose, you can't admit defeat.

He glared at Gu Xu: "Teacher Zhang asked you to tell other students to see what you can say!" ”

"What I say is my business. I am telling you today, not to prove myself to you, but to let Mr. Zhang let me share it with you, and I also want to help you learn. ”

"Okay! I'll see how many people you can understand! ”

Gu Xu ignored him, such a person would not shed tears even if he saw the coffin.

Needless to say, just seconds!

Gu Xu looked at Zhang Xiaoli: "Teacher, let me say it differently." ”

Zhang Xiaoli was surprised: "Teacher Zhang, can I ask Zhang Song and Jia Fanzhen to come up and help me?" ”

Zhang Xiaoli nodded.

Zhang Song and Jia Fanzhen came up together.

For such a thing, Gu Xu would not let Lan Ruosi come.

First, he knew that his little daughter-in-law was shy, and she would definitely be embarrassed on such an occasion.

Second, how could he be willing to let his little daughter-in-law make props?

Zhang Song and Jia Fan were really puzzled.

Gu Xu asked Jia Fanzhen and Zhang Song to stand in his designated position.

After the two of them stood up, Gu Xu fiddled with the projector again, projecting their shadows on the screen.

"Everyone, pay attention, the two of them are standing separately, one on the left and one on the right, are there two shadows?"

"Yes!" Everyone nodded.

“OK！” Gu Xu also nodded, "You understand this!" The two of them form two lines, then, as we said, the triangle is the most stable, and the parallel lines are not stable. We're starting to move now. ”

Gu Xu walked over to Zhang Song as he spoke, and began to move Zhang Song.

Gradually, Zhang Song's shadow on the screen and Jia Fanzhen's shadow coincided.

"Let's look at it now, although it is two classmates, there is only one shadow projected on the screen.

The points that you don't understand are probably because you draw on a plane, there is no three-dimensional sense, and there will be visual errors, so it is obvious. ”

As soon as these words came out, there was an uproar in the audience, and everyone seemed to understand in an instant.

Lan Ruosi exclaimed: "I understand it too!" I was just wondering why it's two lines. ”

Zhang Xiaoli heard Lan Ruosi understand, and nodded silently, "You also understand?" ”

Lan Ruosi said: "Yes, I understand it too! My mind didn't open up before, but after I saw Gu Xu make it, my mind opened. ”

Zhang Xiaoli was a little worried: "You do it for me!" ”

Lan Ruosi then began to draw on scratch paper.

Zhang Xiaoli looked at her drawing process and nodded with satisfaction: "Yes, you did the right thing." ”

Lan Ruosi and Gu Xu understood, and she would win.

As for the other students, how many can be understood counted.

Lan Ruosi said with a smile: "This is thanks to Gu Xu. ”

Her gaze looked at Gu Xu again.

Gu Xu continued: "In addition, there is the issue of spatial imagination. When we draw a picture, it is on paper, and it can be extended infinitely.

For this geometry, let's look at its edges first, and each edge has opposite parallel lines.

After contrast, like the parallel lines we usually draw on paper, they extend like meridians and intersect the North Pole at the South Pole at a great distance. In this way, the problem will be solved. ”

"I see!" One of the classmates said.

"I get it, too!" Another classmate said.

Everyone answered one after another, and everyone understood.

"Okay, you all understand, I can go down!" Gu Xu said and walked towards his seat.

"Do you understand?" Gu Xu asked as soon as he came back.

Originally, I just told the little daughter-in-law about it, but now I tell the whole class, and I don't know if the little daughter-in-law understands it.

"I see!" Lan Ruosi nodded, "I understood halfway through what you just wrote." ”

"You get it." Gu Xu breathed a sigh of relief, as for whether others understood it or not, it didn't matter.

Jia Fanzhen and Zhang Song also sat in their positions.

Jia Fanzhen sighed: "Xiao Sisi is a scholar, Gu Xu is simply a scholar!" Xiao Sisi, I can't help you blow it when I go out in the future. ”

Lan Ruosi smiled: "Gu Xu is already very good!" ”

Lan Ruosi said and looked at Gu Xu.

Zhang Song answered: "Why, Lan Ruosi is a scholar, and Gu Xu is a scholar." ”

"My little Sisi has such good grades and is recognized as a top student. But this time, Gu Xu is better than her, and the one who is more powerful than Xueba is not Xueshen? ”

Zhang Song suddenly said: "Yes! ”

He said and gave Gu Xu a thumbs up: "Learn God, my learning will depend on you in the future!" ”

When everyone saw that Gu Xu had done it, they also praised it.

"Gu Xu is really amazing!"

"I didn't expect Gu Xu's math scores to be so good."

"Gu Xu has taken some kind of elixir, and his academic performance has improved by leaps and bounds!"

Wang Xianchao was very unconvinced when he saw this, what is proud, isn't it just a question! What's the big deal.

Yang Wanli sat down and was also unconvinced: "Wang Xianchao, this idiot, actually lost to Gu Xu, it's really embarrassing." ”

Zhang Xiaoli saw everyone talking and said: "Okay, let's be quiet, students who don't understand, go down and think about it, or ask your classmates." ”

Zhang Xiaoli nodded: "Gu Xu's explanation is very careful, and his thinking is also very correct, after countless times of mirroring, the original model and the one after the reflection have been changed beyond recognition."

Everyone must pay attention to the two points that Gu Xu said just now, the overlapping line and the infinite extension. If you still don't understand something, you can ask Gu Xu, and you can ask Lan Ruosi. I just heard her say it, and she got it. ”

Zhang Xiaoli said and looked at her watch: "It's ten minutes before class ends, I'll say something." Today is the 24th, tomorrow is the Mid-Autumn Festival, and the other grades are on holiday, so we will go to class as usual. All the way up to this Sunday.

October 1st, National Day is Monday, the school is closed for three days, and classes officially start on the 4th. However, after the discussion of the senior third grade group, our senior high school will not have a holiday, and the evening make-up classes will be suspended for three days.

There will be no make-up classes on Sunday evenings, that is, on the evening of September 30th, no make-up classes on the evenings of October 1st and 2nd, and will continue on the evening of the 3rd. Did you hear me clearly? ”

"Hear me."

After that, the bell rang for the end of class.

Everyone packed their school bags and prepared to go home.

As soon as the four of them walked out of the classroom, Wang Xianchao came over again and stopped Lan Ruosi.

Gu Xu said angrily: "What are you going to do!" ”

"Mr. Lan, can you tell me about this topic? Just now, Mr. Zhang said, if you don't understand, you can ask you. ”

Gu Xu smiled disdainfully: "Holding chicken feathers as an arrow, Sima Zhao's heart is known to passers-by." ”

Lan Ruosi didn't have time to speak.

Wang Xianchao said again: "Classmate Lan, I know where your family lives, can I go home with you?" On the way, we can talk as we go. ”

"I'll go!" Zhang Song exclaimed, "You really dare to open this mouth." ”

Gu Xu had a stump in his heart, he actually knew where my daughter-in-law's house lived, this was really hard work.

Lan Ruosi smiled faintly: "I can't speak well, you better ask the teacher tomorrow!" ”

She said she wanted to move forward.

Wang Xianchao said again: "It's okay if you don't talk about the topic, I'll send you home." My family's car is already waiting for me outside, and I asked the driver to take you home first. ”