Chapter 167

Five questions.

In terms of difficulty, it can be divided into three grades.

The third question, the lowest grade, is the easiest of the five questions.

The first question, the second question, the second grade, the difficulty is moderate among the five questions.

The fourth, fifth, and third grades, the two most difficult questions!

Of course, the level of difficulty here is only relative.

These five questions, any one of them, is enough to be used as the finale of the college math competition.

Compared with the first lesson in the math class, the third question that Gu Lu wrote on the blackboard was much more difficult.

Maybe others have already knelt down when they encounter this kind of topic.

But Bizzie felt he could still struggle.

After all, what Mr. Gu requires is that you can get three of the five questions right, not all of them.

Two hours, there is still a chance.

Bizzie decided to start with a strategy that was easy from difficult to easy.

He has not yet confidently tackled the fourth and fifth questions directly.

Although Bi Qi likes to perform, he still has a relatively clear understanding of his own ability.

To put it simply, it is very B-numbered.

It is safest to start with the simplest question 3.

Bi Qi took a deep breath and read through the stem of the third question from beginning to end.

Bi Qi took out an A4 piece of paper, wrote his name, and then wrote a big word "solution".

The whole process is smooth and done in one go.

And then......

Then Bi Qi carefully put the answer sheet in a book, and took a piece of scratch paper.

While thinking about the solution idea in my mind, I deduced the formula on the scratch paper over and over again.

Five minutes later, Bi Qi's eyes lit up, and his right hand suddenly clenched, looking excited.

"Yes, that's how it should be. ”

After taking the answer sheet, Bi Qi pondered for a few seconds, and slowly wrote down the formula line by line on it:

【f(x)=f(t)/0!+f'(t)/1!*(x-a)+f''(t)/2!*(x-a)^2......

............

0=f(0)=-1+f''(t1)/2!x0^2

0=f(1)=......

And because 0≤x≤1, f(η)=max{2/x^2,2/(1-x0)^2}≥8 !]

The third question is relatively easy.

Because this problem can be solved perfectly by using the special form of Taylor's formula, McLaughlin's expansion, and the knowledge of Schlemirch-Roche's remainder.

In about 20 minutes, Bizzie wrote a full page of A4 formulas and successfully solved the problem.

"It's easy!" Bi Qi muttered, and then began to tackle the first question.

For the first question, Bi Qi thought hard for ten minutes before he had an idea.

This question is a very comprehensive one.

Roughly speaking, it examines four areas: elliptic equations, trigonometric functions, differential equations, and vector operations.

The first question has two questions.

Solving the first question requires knowledge of vectors and trigonometric functions, which is not difficult for Bizzy.

The difficulty lies in the second question.

The second question is mainly about ordinary differential equations, which will only be studied in the third book of mathematics.

After thinking about it for a long time, Bizzie realized that the second question should be solved by using the Pika-Lindeloff theorem for solving ordinary differential equations!

It took more than half an hour for Bi Qi to get the first question done, and this time Bi Qi wrote a page and a half of formulas, dense, so that an ordinary person can see the kind of scalp numbness.

Bizzy glanced at the time.

There is still an hour or so to spare.

After some simple thinking, Bizzie decided to challenge the fourth question.

In his opinion, an hour, even if the difficulty of the fourth question is a little perverted, is enough for him to solve it.

When the time comes, I can also prove myself to Teacher Gu.

But it turns out that Bi Qi thinks too much.

Ten minutes later, Bi Qiqiang angrily crumpled the scratch paper into a ball and threw it into the trash.

"Damn, Lao Tzu admits it!" Bi Qi pointed to the fourth question and burst into a foul mouth, then picked up a new piece of scratch paper and listed the formulas for solving the second problem.

It's so hard, it's so hard!

Bi Qi really regretted why his brain was hot just now and he went to solve the fourth problem.

I wasted a lot of time, not to mention, and made my mentality extremely explosive.

After pondering the fourth question for more than ten minutes, Bi Qi really didn't have any thoughts.

Not to mention making this question, I don't even seem to understand the question.

Seeing that time was passing minute by minute, Bi Qi decisively chose to give up.

Let's go back to the second question.

Bi Qi is not strong.

After taking a few deep breaths, Bi Qi adjusted his mentality.

At around eleven fifty, Gu Lu stretched his waist, closed the computer and was about to go to lunch, when Bi Qi came over with a few pieces of A4 paper.

"Done?" Gu Lu took the answer sheet handed by Bi Qi and said with a smile.

Bi Qi nodded, without the slightest expression of excitement, "It's done." However, only the first three questions were made. ”

Gu Lu nodded with a smile, "That's good." If you do all five questions, let alone this semester's math class, I will agree to the next semester's math class if you apply for exemption. ”

After speaking, Gu Lu turned Bi Qi's answer sheet page by page.

Answer, no problem.

After a cursory glance at the derivation steps, there are no major flaws.

Gu Lu returned a few pieces of A4 paper to Bi Qi and said, "Do you want to take the application with you?"

"Bring, bringing. Bi Qi looked overjoyed, and took out a folded application form from his pocket, which was already signed by the counselor.

Gu Lu took it and signed his name.

Bi Qi carefully put it away.

Gu Lu instructed Bi Qi, "Don't think that everything will be fine if you apply for a waiver." A few roommates in your dormitory will tell you that you don't forget to hand in the classwork. ”

Bi Qi's chest thumped, "Teacher, don't worry, I will pay it on time." ”

Gu Lu then spoke, "If you usually collect your homework, you are not there, let someone else do it for you." ”

Bi Qi smiled, "Just Ma Zhengxuan, they are all acquaintances, convenient." ”

"And the last point, which is the final exam. You must take your attitude towards the final exam seriously and never be too casual. Gu Lu finally reminded, "Regarding this final exam, I can reveal a little bit of news to you. ”

"What?" Bizzie wondered.

Gu Lu pointed to himself, "This year's final exam paper is written by me. ”

Bizzie: "......"

Bi Qi subconsciously swallowed his saliva, clasped his hands together, and begged, "Teacher, you must be merciful!"

Bizzie was not worried that he would not achieve 85 points in the final exam, and his grade would be recorded as a failure.

Because he can only take the test paper with 85 points, it is estimated that the failure rate of the whole class can reach half.

His goal is not 85 points, but ...... 95 points or more!

Bizzy wants to select this year's special scholarship.

One of the basic conditions for selection is that no subject final score of 95 points or less is allowed.

If other teachers ask questions, Bi Qi is 100% sure that he will achieve this goal.

But Mr. Gu's words ......

Bi Qi's heart hung in the air.