When the lim is at an absolute value.

The relationship between f(x1) and f(x0) can be denoted as ......

The performance equation can be listed as: 0(f(x0+)))/x.

……

For five days in a row, Fang Chao closed himself in the room and did not go out.

The process of waveguide function is also slowly progressing every day.

Progress 20%.

Progress 37%.

Every day, the operation on the waveguide function is slowly approaching completion under Fang Chao's calculations.

This is not a specific interval function, but just an example of a functional equation that Fang Chao himself thought of.

Although it is not as great as cracking a conjecture, it is a way of solving a specific function, born from an idea, and slowly approaching perfection by manipulation.

Zheng Meiling bought bread and water, put it at Fang Chao's door, and was opened by him and put it directly into the room.

The current Fang Chao can't be disturbed by anyone, fortunately, Fang Chao didn't lock the door, Zheng Meiling occasionally secretly opened the door to a gap, and when she saw that her son was still moving, she was a little relieved that she wouldn't be so nervous.

Day 4.

Day 5.

Progress has reached 72%.

Up to now, the closer you get to the later stage, the equations have already been listed, and the real remaining 20% is just to analyze the equations that have not been solved before, and calculate how to get to this point, which is an in-depth analysis.

On the sixth day, the progress was 97%.

And at 10 a.m. on the seventh day, the progress reached 99%.

Couldn't get any closer!

99%！

This is the limit that Fang Chao can reach, and it is also the extreme that he can do by himself.

Even if Fang Chao was given more time, Fang Chao couldn't get any closer to the waveguide function, he had reached 90% yesterday morning, and he had only completed 7% of his progress in a whole day.

That night, he burst his liver, but it took him ten hours to complete 2% of the remaining 3%.

Of course, this is what he thinks is the perfect function step, and if he wants to rate himself, it must be 100 points, but if he wants to talk about progress, it can only be 99%!

The remaining 1%, that is because this functional equation has not been affirmed by professionals, there must be some gaps in it, but this problem is not something that Fang Chao can find, and his level has not yet reached this step of self-evaluation.

Mathematics LV4 level, unable to complete this step!

Naturally, even if it is someone else, there is no way to make 100% progress on the problem they have in mind, even if a mathematician completes a conjecture, as long as it is not demonstrated, the progress will always be only 99%!

Of course, the highest is infinitely close to 100%, or 99......%.

However, in the field of mathematics, as long as it has not been demonstrated, it is basically defined as 99%.

For seven days in a row, Fang Chao was unkempt, the whole person looked very sloppy, and even his beard grew a little...... This is not yet eighteen years old, and it has already begun to take on the symbol of adulthood.

Fang Chao knew that he had grown up.

Soon he would no longer be a seventeen-year-old minor, and in a few months, he would be an eighteen-year-old adult.

I'm so tired, everyone has become a doctor at the age of eighteen, but what about myself? Still so nothing......

Forget it, let's get the matter in front of you first.

In the case of the waveguide function, he has already completed all the steps himself, but he needs a checker.

This person can't be found in the high school, the level is not enough, although Lao Zheng is powerful, but his strength is physics, and there is no way to provide Fang Chao with a professional opinion in mathematics.

When he thought of this, Fang Chao took out his mobile phone and dialed a call.

The phone rang a few times before it was answered, and a slightly surprised voice rang from there, "Chao'er, what's wrong?" Why did you suddenly remember to call me? Haven't I been gone for less than 10 days? Do you want me to teach you the technique of picking up girls? No problem, but when did you get the hang of it? ”

Listening to Shen Lang's familiar tone, Fang Chao felt cordial, even his body, which had not rested for seven days, also felt a warmth at this time.

is not afraid of fighting alone, the most feared is that no one can share the results after fighting alone.

If you want to have an appetite, you have to have enough attainments in mathematics, and among the people Fang Chao knows, there is only Shen Lang.

"No, Brother Lang, that's right, I've been thinking about a question these days, that is, if there are two functions with equal approximate values, when they are in an equilibrium, whether there is a solution and multiple solutions, or no solution.

On the other hand, this question is somewhat similar to Schrödinger's cat, but quantum mechanics is too complicated, and what I am studying is only a function question, and its answer is in an interval, so there are not two ultimate answers, either life or death, when I think of this function, it took seven days to list its various equations, but unfortunately my level is limited, I don't know if the direction of my research is wrong, so I want to ask Brother Lang you to help me see, I don't know Brother Lang, you have time? ”

Shen Lang gave Fang Chao a great help in the ten days he came to Rongcheng, and now that he is gone, Fang Chao has something else to ask the other party for, speaking of which, Fang Chao feels that he owes Shen Lang a lot, and Shen Lang almost does his best to help him without asking for anything in return.

Now that he has a request for the other party, Fang Chao is somewhat embarrassed, but apart from Shen Lang, he doesn't know anyone else at all.

Professor Lin can, but will he come to see an analysis of a function problem written by a high school student?

If you don't reach a certain level, you won't have that qualification.

It's like if you want to publish a mathematical work in some well-known mathematics journals, you also need to go through layers of screening, and if you can't even pass the first level, let alone the follow-up.

After listening to Fang Chao's words, Shen Lang said with a smile, "You kid can, I didn't have your level in high school, I was able to ask questions and answer questions, I don't have time today, but you can send it to me first, and I'll help you see it tomorrow." ”

Shen Lang agreed to Fang Chao's request again, which made Fang Chao very happy and excited.

"Thank you, Brother Lang."

"Don't be too happy too early, if you're a pickled girl, I'll accept this thanks, but when it comes to academic issues, I won't be merciful, and if the last function is full of mistakes and omissions, I won't be polite to you."

"I know, so please Brother Lang."

[Fang Chao: ???????????? Ask for a subscription!???????? Come on!! 】