At 8 o'clock in the morning, try it out.

The test papers in the competition are different from the college entrance examination papers. Since there are few questions and few types of questions, the test papers with questions are also very small.

The 8 fill-in-the-blank questions and 3 answer questions occupy only one-quarter of the four-sided mathematics test papers.

"Suppose set A={2,0,1,3}, set B={x丨-x∈A,2-x2?A}. Then what is the sum of all elements in set B?"

This is the first question of the fill-in-the-blank question, which is a collection question. It is very simple, and the simple ones don’t look like a competition question.

After reading the question stem of this question, Zhao Xiancai, who had not yet entered the "immersive learning" state, calculated a few times on the draft paper and wrote the answer.

He solved this problem for only a minute, and this is still under normal circumstances.

After solving the first question, Zhao Xiancai quickly focused on the second question.

"In the plane rectangular coordinate system xOy, points A and B are on the parabola y2=4x, satisfying vector OA* vector OB=-4, and F is the focus of the parabola.

Then what is S△OFA*S△OFB equal to?”

The second question is a vector question, because F is the focus of the parabola, it is easy to find its coordinates.

丨y1y2丨You can use the conditions of vector OA*vector OB=-4 and points A and B on the parabola y2=4x, and this question is also not difficult.

After solving the second question, Zhao Xiancai started to do the third question again.

When reading the third question, Zhao Xiancai obviously felt that the thoughts in his mind suddenly became much clearer than before. This is the effect of the skill [Study hard] begins to work.

After reading the third question, thanks to the effect of skill [Study hard], Zhao Xiancai didn't even move the draft paper this time, and directly calculated the result in his mind.

Next is the fourth question, the fifth question...

As the calculation amount of the subsequent questions gradually increased, the calculation process was more complicated than the previous questions, Zhao Xiancai once again began to calculate on draft paper.

When Zhao Xian finished writing eight fill-in-the-blank questions, ten minutes had just passed.

However, Zhao Xiancai, who was in the state of "immersive learning", did not notice whether time passes quickly or slowly. Soon he started to answer three more questions.

The first question of these three answers is quite simple, and the second and third questions are somewhat difficult.

No wonder the first answer was 16 points, and the last two answers were 20 points.

"…In summary, the total of the positive real number pairs (a,b) obtained is {(a,b)丨0＜b≤1,0＜a＜1,2a b≤2}."

After writing the last question, Zhao Xiancai breathed a sigh of relief and stretched.

From the fill-in-the-blank question on the third question to the answer to the last question, Zhao Xiancai could be said to have finished writing it in one breath, without any pauses in the middle.

After writing this last question and preparing to look up at the time, Zhao Xiancai could clearly feel that his previous state had disappeared.

If he had just written the second test paper now, he would probably have to brew for a while before he could get into the same state as he had just now.

Before he entered the same state as before, his answering questions would definitely be much slower.

"Huh? Less than thirty minutes have passed?

In other words, there are more than fifty minutes left to end this exam?"

After seeing the time displayed by the clock hanging on the wall above the blackboard, Zhao Xiancai himself was a little surprised.

Fortunately, Zhao Xiancai kept in mind Lin Guangqiang's teachings and did not hand in the paper in advance, but checked the test paper again.

When he checked the papers and looked at the clock hanging above the blackboard, he found that the exam was only over thirty minutes before the end of the exam.

"I've checked it all, and no problems have been found.

Even if you hand in the paper in advance, you can't leave the examination room early. You have to find something to do. You can't sit here and stay blank for half an hour, right?"

After thinking for a few minutes, Zhao Xian put his mind on the last three answers.

"Since I have nothing to do, why don't I try to find the second solution for these three answers?"

Thinking of this, Zhao Xiancai did it as soon as he said that, and immediately began to think about other solutions to these three answers.

Dingling, Dinglingling...

Thirty minutes passed quickly, and as the ringtone rang, Zhao Xiancai reluctantly handed over the test paper.

He had just thought about the second solution to the last question, and wrote a little on the draft paper, and the ringtone rang.

After handing over the test papers, the invigilators counted the test papers, and after leaving the examination room, the candidates were finally able to move freely.

It was not until this time that Zhao Xian ran outside, took out the draft paper from his schoolbag outside, walked back to his seat and began to calculate.

He stopped writing until halfway through the exam.

When Zhao Xiancai was doing selfless calculations, many students from this examination room were surrounded by him.

"Although this method is a bit cumbersome, it's not bad, but it's a pity that it's ten minutes late."

After Zhao Xiancai calculated the exact same result as he used the first solution, one of the students watching said.

"You have calculated this question?"

Listening to the appearance of the classmate's old god, a candidate watching next to him asked him.

"No."

The candidate shook his head, which aroused the contempt of other candidates around him. You haven't calculated it yourself, so why don't you say a yarn?

"But I didn't figure it out. Can't I even read the answer?

At least I didn't see any problem with his problem-solving process.

And you can't even write a piece of draft paper, which is really a bit cumbersome.

Anyway, if I were asked to write, just writing the disintegration process, I guess it would take him at least twice as long to finish it."

The first person who spoke to him defended himself when he saw the contemptuous gaze coming from around him.

After finishing the question, Zhao Xiancai also took back his schoolbag with satisfaction and went to the bathroom.

"The question he calculated was the last question to answer the question, which means that he should have finished writing the previous ones. This is very likely to be a great master."

"Even if he didn't have a single point in the last question, as long as the previous ones are right, he will get 100 points in one try."

After Zhao Xiancai left the examination room, the candidates who had watched the examination room had dispersed one after another, and some of them sighed to each other.

It seems they are from the same school.

In fact, in this league, there are not many people who can meet their classmates in an exam room.

After all, the good high schools in other cities are not comparable to high schools in small counties like Chengxian No. 1 Middle School. Those students who participate in the league in good high schools are obviously much more than Chengxian No. 1 Middle School.

Otherwise, it would be impossible to gather more than a thousand people to participate in this league by relying on just a few people from provincial demonstration high schools in each county.

After returning from the bathroom, Zhao Xiancai began to close his eyes in his seat to rest, so as to restore more energy for the next second trial.

When the exam was about to start, Zhao Xiancai turned out the math paper he rewarded when he completed the task in his mind and started reading it.

His purpose is to get into the state as soon as possible, and he doesn't have to prepare any more when the papers for a while and the second test is handed over.
Chapter completed!