Reborn Xueba, you don't really think that studying is difficult, do you?

[Solution (2): The title is equivalent to f(x)=1 on (0, +∞) and there are only two solutions. 】

[When 0
[At this time, lna>0, a/lna>0, change the domain of f(x) to [0, +∞), and f(0)=0 at this time. 】

【…】

【令g(x)=x-1-lnx，x∈（0，+∞），g’(x)=1-0-1/x=(x-1)/x。】

【所以g(x)≥g(1)=1-1-ln1=0。】

[From a>1 to get lna>0, get: g(lna)≥0. 】

[From Bernoulli's inequality...]

[From the monotonicity of f(x), it can be seen that f(x)=1, there is a solution on (0, a/lna) and (a/lna, +∞). ]
[In summary, the value range of a is (1, e)∪(e, +∞). 】

……

It's that simple when you're done.

The focus of this question is nothing more than the application of knowledge points such as derivation, isomorphism, and extremum point offset.

Here, Lin Bei also used Bernoulli's inequality, everyone must know this, right?

Bernoulli's inequality, also known as Bernoulli's inequality, is for scaling from a power function to a linear function.

It may be rarely used on weekdays.

But in the final question of the college entrance examination, especially the second question, there are many opportunities to use it.

Of course, it is not necessary to use Bernoulli's inequality to make the second question of the finale of this paper.

In fact, there are many ways.

As long as you have enough understanding of isomorphism, exponential tangent scaling and hidden zero point, you can see it at a glance by drawing a picture.

Besides.

You can also use L'Hopital's rule.

However, high school does not seem to learn L'Hopital's law, which belongs to university knowledge, so the general teacher does not allow it to be used, unless you prove it yourself, otherwise there is a high probability that points will be deducted.

all in all.

This derivative finale question is difficult for ordinary people.

But at the height of Lin Bei, is it so difficult?

The clock on the blackboard points to 2:28, only 5 minutes have passed since the end of the previous question.

The finale of the derivative can be done in 5 minutes.

I don't know... have you seen it?
This kind of hand speed, not to mention being single for 1000 years, even if you have been single for 10000 years, I'm afraid it will be far behind!

"Huh, this paper is really boring!"

Lin Bei breathed a sigh of relief, feeling a sense of loneliness between his brows.

In fact, these questions are too simple, even if it is the final question, he doesn't need to think too much.

It is no exaggeration to say that the only thing that limits his test speed is his hand speed, otherwise he can go faster.

Originally, he was full of expectations for this exam.

After all, this was the first formal exam he took after his rebirth, and he wanted to use this to test his own strength.

But now, I feel a little disappointed.

"This year's question maker is not good enough?"

"It's okay for the Chinese questions to be simple in the morning, but now the math questions are also like this. I feel like I'm fooling people."

"Don't tell me, is this sending elementary school students away?"

"ヽ(｀⌒メ)ノ!"

Lin Bei spread his hands and turned his attention to the last two questions of the test paper, which are the elective questions.

Optional exam questions.

As the name suggests, you can just choose one.

Do whatever you know how to do, don’t try to do all of them, because it’s useless.

If you do everything, you will only be scored according to the first question when marking the paper, which will only waste the examinee's time.

But what Lin Bei lacks most now is time.

After all, the math test takes 120 minutes, and it took him only 28 minutes to do it now, which is less than half an hour.

and so……

He solved the two questions in one go.

only see...

Question 22, Coordinate System and Parametric Equation.

Question 23, Inequality Selected Lectures.

Many candidates often fall into a misunderstanding of tangled thinking when they see the last two elective questions.

Is this the choice of coordinate system and parametric equation?Or choose to do inequality lectures?
Some people say that the former is the best choice.

Because the question is scored by point, even if it is not a plenary meeting, you can write a one or two, but the inequality is different.

Some people say that the latter is the best choice.

Inequality after all?

The first question is to send points for routines.

Although the second question has changed a lot, it can't escape the changes of those formulas such as Cauchy's inequality.

all in all.

It is the public who says the public is right, and the mother-in-law says that the mother-in-law is right.

No one can win the quarrel, and even more people have headaches.

But Lin Bei naturally didn't need to worry about these, after all, he solved both questions without any effort.

2:30 minutes, coordinate system and parametric equation, dead.

2:32 minutes, selected lectures on inequalities, died.

2 minutes a piece, add up to only 4 minutes.

Don't ask him why he is so fast, because he is strong enough, so he is naturally domineering.

then.

He lay down on the table and fell asleep again.

It's not too much to recharge your batteries and prepare for the re-communication with Zhao Qinghan after the exam, right?
Invigilator: "←_←??"

Surrounding students: "→_→??"

Seeing this scene, everyone was speechless.

"He fell asleep, and he fell asleep again?"

"For the Chinese test in the morning, it's okay for Lin Bei to go to bed after four, five and ten minutes of the test. Now the math test has only been over half an hour, and he actually fell asleep on the table again?"

"This...isn't it incredible?"

"No matter how strong he is, it's impossible to do it so fast, right? Unless he doesn't know anything and just cools off."

"Sure enough, Lin Bei is still the same Lin Bei. He was a bad person for a day, and he will be a bad person for the rest of his life. His nature of learning water is hard to change."

"Three ten minutes, it's a miracle to get thirty points in the test. This time, he and Yang Juntian's bet is probably lost."

"..."

Many people in the class shook their heads.

This includes Zhang San, Li Si, Wang Teng and Zhao Dali.

Originally, Lin Bei performed very well in the past half month and has been studying hard. Everyone thought that there might be a close battle between him and Yang Juntian.

But in the end, he was evenly matched and didn't see it, but only saw Lin Bei sleeping soundly, and the broken pot broke.

Even though they had just passed the second subject and didn't start science and foreign language, everyone could already predict the ending.

There is no doubt that Yang Jun is in the top ten of the class.

Give it a go, maybe you can make it into the top five.

The total score should not be less than [-] points.

And Lin Bei was determined to be the last one, the total score of the six subjects could exceed [-], because the sun came out from the west.

In this regard.

Undoubtedly, Yang Juntian was the happiest and proudest.

He was almost the same as in the previous language test, almost laughing like a pig, and couldn't even cover it.

"Lin Bei, I really think highly of you!"

"It's a pity that I was a little worried before the exam, but now it seems that I won this round!"

"When the time comes, you should obediently sing to me in front of all the teachers and students in the school, and sing to me Happy and Shout out to Ultraman Tiga!"

"After you make a fool of yourself and lose face, I don't think you still have the face to cling to Zeng Xi!"

"Ahahahahahahahahahahahahahahahahahaha!"