Midsummer evening opened his notebook and wrote something on it with a pen, and replied lightly, "No." ”

Midsummer: ......

The next trip,When Sheng Xiaqing was brushing the questions,Midsummer evening was busy with her own things,While paying attention to Sheng Xiaqing's answers,When she found that Sheng Xiaqing frequently made mistakes in a question type,She flipped the book to a blank space,"Brush the ......" wrote some key points on it。

In the middle of the summer, when he was not assigned to the study task, he saw that the eldest sister really didn't plan to give him a roll, so he closed his eyes and began to make up for sleep.

Midsummer just gave Sheng Xiaqing this paper is mathematics, although the liberal arts class she chose for Sheng Xiaqing, the mathematics test is also the liberal arts mathematics, and the question type will not be too difficult.

But Sheng Xiaqing is too weak in mathematics, so Sheng Xia Wan plans to catch her first, and other liberal arts questions that need to be memorized are easy to overcome.

Sheng Xiaqing had a headache when she saw the math papers, but she still did it very seriously, and tried her best to do one more problem and calculate one problem, some of the problems she really didn't know, and she would be able to solve one step at a time. The time to do the questions in earnest always flies, and before you know it, an hour has passed, and the alarm clock set in advance for midsummer evening has gone off.

Midsummer evening closed the notebook and looked sideways at Sheng Xiaqing, Sheng Xiaqing was still frowning and thinking about the topic, Midsummer Wan lowered her head slightly and looked at her volume, there are not many questions with answers written on the volume, but Sheng Xiawan saw Sheng Xiaqing's seriousness from the scratch paper on the side of the volume, and that was enough.

Midsummer evening asked softly, "Do you have the answer?" ”

Sheng Xiaqing shook her head helplessly, "Eldest sister, I really tried my best." ”

"Well, I can see it, I'll tell you the rest!"

In the following time, Midsummer Evening answered all the questions that Midsummer Qing would not know with Midsummer Qing one by one.

This paper is a basic paper, and it is not very difficult, as long as you know the idea of solving the problem, it is easy to solve.

It's just that Sheng Xiaqing was relatively weak in mathematics when she was studying, and now she has graduated for several years, and she has forgotten a lot of knowledge points, especially the knowledge points related to functions, and she is basically losing them.

This is a very bad thing, because function is a main line throughout high school mathematics, and it can instinctively intersect and synthesize with many knowledge contents, so it has always been one of the core contents of the college entrance examination.

Midsummer was very patient and talked to Sheng Xiaqing, "Xia Qing, look at this problem, it is looking for the definition domain of the function.

When you solve the problem, the conditions are not sufficiently considered when finding the definition domain of the function.

You ignore the condition that the denominator is not zero, and mistakenly think that (x+1)O=1 is true for any real number, so you are wrong.

Well, this is a list of points that you should pay attention to when finding the domain of the function definition, you remember it, and pay attention to these points when brushing the questions later, you will not make a mistake when finding the domain definition. ”

Sheng Xiaqing took the paper handed over by Midsummer Evening, and ten precautions were clearly written on it.

1. When it is an integer or an odd root formula, the definition domain can take an infinite value;

2. When it is an even radical formula, the number of squares to be opened is not less than 0;

3. When it is a fraction, the denominator is not 0, and when the denominator is an even radical, the number of squares to be opened is greater than 0;

4. When it is exponential, the base number is not 0 for the exponential power of zero or negative integer exponential power;

5. When it is formed by the combination of some basic functions through four operations, its definition domain should be the set of values of independent variables that make each part meaningful, that is, find the intersection of the set of definition domains of each part;

6. The definition domain of the piecewise function is the union of the set of values of the independent variables on each segment;

7. In addition to making the analytic formula meaningful, the function established by the practical problem needs to consider the requirements of the practical meaning on the independent variables.

8. For functions with parameter letters, the values of the letters should be classified and discussed when finding the definition domain, and it should be noted that the definition domain of the function is a non-empty set.

9. The true number of the logarithmic function must be greater than zero, and the base number must be greater than zero and not equal to 1;

10. The cutting function in the trigonometric function should pay attention to the restriction of diagonal variables.

"Thank you, big sister, I'll remember them." Sheng Xia Qing sincerely thanked her.

This note is handwritten not printed, I think it was just written by the eldest sister, the eldest sister was obviously busy with her own affairs just now, but she still took the time to pay attention to her own situation and sort out the key points for herself, which couldn't help but remind her of the time when the eldest sister took her at home before.

When Sheng's father and mother were absent from daily life due to work, Midsummer Evening, who was the eldest sister, really brought her younger brothers and sisters very well, especially Sheng Xiaqing, who was only two years younger than Midsummer, and the time she spent with Midsummer was two or three years longer than that of Midsummer.

Whether it is in life or academics, Midsummer Night takes care of her younger siblings very much, so before Midsummer Night didn't go out to college, Sheng Xiaqing's studies were okay because of Midsummer Evening's tutoring for her.

Everything has changed unsatisfactory since she was in her second year of high school and was admitted to college in the middle of summer and went to other provinces.

At that time, although she was in the field on the summer evening, she would still call Xia Qing every week, and it was certainly not as good as face-to-face communication through telephone communication, plus she was very busy in the summer evening, and she entered the student union as soon as she entered the university, and she became the president of the student union in her sophomore year.

Sheng Xiaqing was thinking that the eldest sister was busy, don't waste the eldest sister's time, and on the one hand, she was busy on the one hand, and because she thought that Sheng Xiaqing had grown up, and she was in charge of so much, so she slowly let go.

However, at that time, Sheng Xiaqing was in the second year of high school when she had just divided her subjects, and there was no pillar around her, so she couldn't adapt to anything, and her grades plummeted.

I didn't study well in the second year of high school, and when she got to the third year of high school, she would only understand those questions even more.

In this state, in the first semester of her junior year of high school, she and her classmates went to the film and television city in Linshi to play, but was temporarily pulled by a crew to be a group performer.

At that time, she just played a passerby, but since then she has liked acting, and she has less heart to study, she began to frequently ask for leave to go to the film and television city to wait for an opportunity to play tricks, just when she was playing tricks, she met her current agent Sister Hua, and has since become a member of the entertainment industry, as for her college entrance examination, a person who has not taken much classes in the whole year of high school, it is conceivable what her grades will be.