Xueba, I beg you to go and escort him quickly!

"It's like this..."

Xu Heng probably understood what Fang Zhonggui meant.

The question I asked before was too difficult and was rejected.As for Fang Zhonggui, he has been busy with the physics competition for college students recently, so he wants to entrust Xu Heng with one or two more questions for the postgraduate entrance examination.

"Student Xu Heng! I really have no skills! I don't want to be irresponsible to those classmates, so I can only ask you for help!"

Thought a university professor!

Do everything with such seriousness and rigor!

He is responsible for everything he does.

"Actually, I can entrust it to other professors, but after thinking about it, I still want to ask you for help!"

Xu Heng's status and importance in Fang Zhonggui's heart surprised Xu Heng.

Fang Zhonggui's words completely showed that Xu Heng was more trustworthy than those physics professors.

Xu Heng, "Professor Fang, you are exaggerating!"

Fang Zhonggui, "No, no, no! No exaggeration! No exaggeration at all! Student Xu Heng, you don't know yourself well enough!"

"Also, congratulations on winning the gold medal in the Olympiad!"

Xu Heng, "Thank you!"

Yue Pingting watched the whole process, the more she watched, the more she didn't understand.

"Why is the professor looking for you? Don't you find it troublesome?"

"Is the nature different from that of Professor Zhu who came to the house before?"

"Even, this Professor Fang is not as good as Professor Zhu! Anyway, Professor Zhu came to your house to talk to you in person! This..."

Xu Heng raised his hand and pinched Yue Pingting.

"Ah! Smelly Xu Heng! It hurts!"

Xu Heng rolled his eyes, "You girl, what do you know! Professor Fang and Professor Zhu are different in nature!"

"Professor Fang simply! If he doesn't bother you, he won't bother you. If he has a way, he won't bother me. Professor Zhu is different. That guy is trying to trick me."

Yue Pingting, "???"

She didn't understand this and was stunned.

"What are you waiting for, come up!"

Yue Pingting, "!!!"

……

A night without dreams.

Xu Heng got up early and came to the study.

In the study, he came as soon as he picked up a pen.

To take the front view and several different side images of the object on one photo at the same time, you can put two upright large plane mirrors AO and BO behind the object, so that the object and its images on the two planes can be captured camera, as shown in figure a.Figure b is a top view.

The circle P with the arrow in Figure a represents the head of a person (its size is much smaller than the length of OC), the white semi-circle represents the face of the person facing the camera lens, and the black semi-circle represents the hair on the back of the head , the shoulders represent the hat on top of the head.

If the angle between the two plane mirrors is 72, the center of the human head is just located on the bisector of the angle between the two plane mirrors, and the distance from the camera to the person is far greater than the distance from the person to the plane mirror.

(1) Try to mark the orientation diagram of all images of P in Figure b;

(2) Draw all the images obtained on the photo in the box in Figure c (use blank and black to represent the face and hair, and use arrows to represent the hat on the head).

After writing the question, Xu Heng wrote the answer without any hesitation, and even drew a picture.

(1) According to the angle between the beam plane is 72, and the imaging law of the plane mirror..., the center of the image of P and P is exactly the vertex of a regular pentagon, marked in Figure b...

Halfway through writing, Xu Heng put down his pen, turned around and went to the bathroom.

Sometimes, when the feeling comes, it cannot be stopped.

Coincidentally, Xu Zongyun also woke up early, intending to come to Xu Heng.

As soon as he went upstairs, he saw the door of the study room was open, and Xu Heng came out of the study room.

"Brother...｀ ~..."

Xu Heng, "Wait for me in the study, I'll be back later."

Before Xu Zongyun could answer, Xu Heng disappeared before his eyes.

Xu Zongyun could only go to the study and wait.

And the reason why he got up so early was because of the new environment on the one hand, and the news from the group on the other hand, which made Xu Zongyun a little angry.

They had a discussion about Xu Heng in the group.

Everyone felt that what Xu Zongyun said was wrong.

"The Internet has memory! If that Xu Heng is so powerful, how could he not be able to find anything?"

"Yes! Even if this matter has passed for a long time, it should be able to be found!"

"Also, who of you has ever heard that the gold medal in the International Mathematical Olympiad was delivered to your door by someone in person?"

"Isn't the International Mathematical Olympiad held abroad? After the competition is over, aren't the prizes awarded directly?"

"Yup!"

"..."

In short, everyone is very suspicious.

Xu Zongyun came to Xu Heng mainly because he wanted to know the specific situation, and at the same time, he wanted to prove to those people that Xu Heng was real!

Walking into the study, Xu Zongyun saw the question on Xu Heng's desk at a glance.

He looked carefully.

The next second, he was stunned, and then, his mind was full of question marks.

"???"

What kind of subject is this?

Looking at these words, I know them all!

The combination of these words can also be understood!

But why just don't know how to solve the problem?

He has no way of doing it.

"Oh my god! It turns out that my brother is doing this kind of problem!"

In Xu Zongyun's cognition, Xu Heng found this question by himself, and then he answered it himself!

So without thinking too much, he took a photo of the topic and sent it directly to the group.

"Come to see my brother early in the morning, he is doing this kind of question! Anyway, I am confused! Everyone, can you do it? @全部members"

As soon as this news comes out.

The group fell silent.

Not everyone is awake!

Everyone in the group, even if it's winter vacation, will get up very early to study and read.

They will not miss any opportunity to learn.

A few minutes ago, they were still discussing the topic!

Now that Xu Zongyun sent out the topic, they were all silent.

Because of what?

Because after they saw the title, they would not!

Xu Zongyun is also ruthless in his work!

Don't give them a chance at all!

As soon as he came up, he just posted pictures and then spoke.

Don't even give them a chance to slap them in the face!

On the spot, someone watched the news, and the veins on their foreheads twitched violently.

"!!!"

"What an air! Really!"

"It's poisonous!"

"Xu Zongyuan, you just find a question, do you think you can coax us here? Hehehe!"

"I'll look for this question on the Internet! If I find it and have the answer, I don't rule out that you did it on purpose!"

They didn't dare to send messages in the group, so they could only mutter through the screen.

But after looking around, I couldn't find it.

"Fuck! What's going on?"

Finally someone couldn't help it, and asked directly in the group, "I couldn't find the question at night, Xu Zongyun, where did your brother get this question?"

Even open group voice directly.

Xu Zongyun was not afraid and answered directly.

Someone shouted, "Come here! I want to hear your explanation! Xu Zongyun, tell me, I can't find this question online. How did your brother find it?"

"Don't tell me, it's in the materials! I can be sure that this is not what we learned in physics in high school..."

I'm talking!

When Xu Heng came back, Xu Zongyun also had doubts about this.

Holding up his phone, he asked Xu Heng directly, "Brother! Where did you get this question from?"

Xu Heng yawned, "I made it myself, what's wrong?"

I!since!Has!out!of! ——

Five words!

Words are like bombs, in Xu Zongyun, the minds of all the students in the group who have turned on the voice have exploded.

Make your own question? !

Depend on! ! !

how can that be!

He is just a student, how could he have the ability to ask questions!

What's more terrible is that the questions he asked are not at all like what high school students can do!

Not only those people in the group were stupid, even Xu Zongyun was also stupid.

"Wait! Brother! What are you talking about? You made this question? No, you made the question, why did you do it yourself?"

Xu Heng rolled his eyes, "Have you ever seen someone who asked a question by himself and didn't provide an answer?"

"I...￥#@%!"

Xu Zongyun couldn't react for a while.

"Brother! Then what are you doing with the question? Amuse yourself? Or...! What is your question?"

Xu Heng, "Physics problem!"

Xu Zongyun, "%￥%##￥￥..."

"No! Brother! I mean, is this question in the high school category, or...?"

Xu Heng sat down and continued to answer questions.

While answering the question, he said, "University question, a question for a university professor. He is working on a college student competition recently. The postgraduate entrance examination questions can only trouble me."

What the hell!