"Student Yang Dongqing, do you know what your greatest responsibility as a student is?" Su Mu interrupted calmly.

"What are you trying to do again!?"

"As a student, your biggest responsibility is to study! And you, Yang Dongqing, as the last student in the class, have seriously dragged down the class. As the class monitor, I have the obligation to provide you with after-school tutoring." Su Mu pushed his glasses, holding a thick book in his hands, and the words "excellent in both character and learning" were almost written on his face.

"Sumu! You are a psychopath! I can't learn anything from you!"

Su Mu shook his head in disapproval: "Your study attitude is very bad. It seems that I must motivate you."

As he spoke, he took out a math exercise booklet and placed it in front of Yang Dongqing.

"Come on, solve this trigonometric problem. The formulas you need are all in the book."

"I'll untie you..." Yang Dongqing was about to curse, but Su Mu's next sentence made his face change suddenly.

"If you can't do it within fifteen minutes, I will cut off one of Miss Jasmine's fingers." Su Mu said with a smile.

Yang Dongqing raised his head suddenly, his face full of anger: "You dare! If you dare to touch Jasmine..."

"Hush! Be patient. I always keep my word. If I say I will cut off one of her fingers, I will never cut off two. Now you have the chance to save her. If you really love her and don't want her to get hurt, then solve this trigonometric function.

It's just a trigonometric function. You've learned it in class, and the textbook is right in front of you. If you still can't do it, don't blame me.

Now, start the clock.”

Su Mu smiled and took out a pocket watch from his arms. The dark gold pattern on it shone exceptionally brightly under the light. He placed the pocket watch on a table not far away and then left.

Yang Dongqing kept cursing, but after a while, he shifted his focus to trigonometric functions, because he knew that Su Mu, this madman, could do anything.

"Phew! It's just a trigonometric function. It's very simple." He took a deep breath and examined the question carefully.

[Given that in ΔΑΒC, ∠A=60°, a=3, b=root 3, find the size of ∠B. ]

Time passed slowly, one minute, two minutes, three minutes...

“Ahhhh!! Fuck fuck fuck! How big is this pussy?”

There is a saying that goes, "When pushed to the limit, people can do anything." But this is obviously wrong, because math problems cannot be solved. If you can't do it, you can't do it.

Fifteen minutes later, Su Mu walked into the dungeon gracefully, leaning on a cane, holding a crystal goblet filled with bright red wine.

"Student Yang Dongqing, do you have an answer?"

Yang Dongqing, who was obsessed with mathematics, suddenly raised his head. At this moment, his mental state was very bad, bloodshot in his eyes like spider webs, and he kept muttering: "sinB=b×sinA÷a, which is equal to the square root of 3 times sin60°......."

"Fifteen minutes will be up soon."

"Don't make a noise! ​​I'm almost done with it. SinB = 1/2! Because a＞b, so ∠A＞∠B, and because sinB = 1/2, so..."

Yang Dongqing's expression suddenly shocked him, and he blurted out an answer: "∠B=30° Hahaha... I figured it out!!"

Pah pah pah......

Su Mu clapped his hands with a look of satisfaction on his face: "Congratulations, classmate Yang Dongqing, you saved one of Miss Jasmine's fingers."

However, before Yang Dongqing could be happy for too long, Su Mu took out another math problem: "It's still fifteen minutes. If you can't solve it, I will cut off one of Miss Jasmine's toes."

"Sumu! You bastard! What on earth do you want to do?!"

Su Mu smiled slightly. He found that Yang Dongqing's mental state was still too good and he needed to do a few more math problems.

"The time limit is 15 minutes."

After saying this, he walked away with his cane.

After venting his anger, Yang Dongqing, who was on the verge of a mental breakdown, had to turn his attention to a new math problem.

After taking a glance, he felt his eyes go dark.

【1, 3, 8, 20, 48, 112, 256........

(1) Please find the general formula of the sequence.

(2) Find the 20th term of the sequence.

(3) From which term does the sequence start to be greater than? 】

"Sumu! I ****"

......

......

The next day, Yang Dongqing couldn't sleep all night.

Because he worked on math problems all night, his math attainments have greatly improved. He has now mastered the trigonometric function formulas, arithmetic progressions, geometric progressions, linear equations with two variables, and so on ... advanced math secrets.

At this time, his mental state was almost collapsed, his eye sockets were sunken, his face was numb, and his eyes were dull.

The group of young ladies from yesterday came again, but no matter how they danced, Yang Dongqing’s eyes could not move at all.

In the monitoring room, Su Mu saw that the time was finally right and he could start hypnosis.

Everything he had done before was to destroy Yang Dongqing's spirit, especially the last math problem. Only a poor student could understand the pain of racking one's brains and still not being able to come up with an answer. It just so happened that Yang Dongqing was a poor student.

The mental resistance of extraordinary people is very high, and their spirit must be weakened to the extreme to ensure the success rate of hypnosis.

This time he was going to do deep hypnosis, not the previous psychological suggestion.

Psychological suggestion is only a shallow level of hypnosis. The hypnotized subject still maintains his own thoughts, but will make corresponding choices or reactions under the psychological suggestion.

Deep hypnosis is like hypnotizing the members of the Viper Gang, which can completely distort the mind of the hypnotized person. However, this deep hypnosis is not long-lasting and needs to be deepened every once in a while. Perhaps only when his mental strength becomes stronger can he achieve permanent hypnosis like a mental stamp.

Boom!

The dungeon door was opened again.

Yang Dongqing, whose eyes were already blurry, heard the sound of the door opening. His whole body trembled as if by reflex, and an expression of extreme fear appeared on his face.

"No...No! I don't want to do math problems anymore! Ugh..."

As he spoke, Yang Dongqing actually began to retch.

Su Mu was very satisfied with this, "Student Yang Dongqing, it seems that you have fully absorbed and digested the mathematical knowledge, and now you are a little full.

It looks like we can move on to the final phase.”

Yang Dongqing seemed not to hear anything, and kept muttering involuntarily: "sin, cos, tan, cot......"