When it comes to age, Qingyun is a junior, and they can wash at will, which is a kind of family-like closeness.

But when it comes to the status of the rivers and lakes, although Qingyun is far inferior to them at the moment, as the actual controller of a large group, he is qualified to sit and discuss with them.

It's a bit uncomfortable.

The most important thing is that the topic of the chat is not easy to grasp.

In the past, when I talked about career and work with Qingyun, they could give me any guidance.

And now...... The three brothers of the Qin family are not stupid, no matter how much they point fingers at Qingyun at this time, let alone Qingyun, their own elders will stand up and express their protests.

This is purely to cause trouble for his niece.

Fortunately, there are two quirky twins in the living room.

"Brother-in-law, hurry up and tell us about functions, we're all going to be shut up by high school math."

After that, the two twin beauties came to drag Qingyun's arm.

When they gave a lecture last time, the two daughters admired this brother-in-law who had not yet passed the door, and now that they encountered difficulties, they naturally hurried to ask for help.

Qingyun blinked his eyes, and under the urging of the brothers of the Qin family, he happily came to the courtyard.

Mainly, he didn't know what to talk to them about either.

There is a generation gap.

And the two little beauties, there is no ditch.

"Brother-in-law, can you help us sort out the functions? This f(X) makes me want to give up math! ”

Qin Shiyue pouted, and her immature little face was full of unhappiness.

People are more angry than people.

Originally, they thought that they were only a little inferior to their sister Qin Manman in mathematics, but who knows, after starting to preview the content of high school, they found that it was not a little worse.

Huating is the pioneer area of many changes in Huaguo.

Unfortunately, so is education.

Qin Shiyue and Qin Shiwan happened to encounter the pilot of 'two exams and one exam' for the graduation examination and the entrance examination, and the difficulty of the middle school examination questions was reduced by a cliff.

This kind of change is to put an end to deviations, difficult problems, and strange problems, and focus on the basics.

The intention is good, but it can also give people an illusion.

In fact, there is also a gap between the full score and the full score.

Just like Qin Manman's words back then, "We can tie in mathematics because the full score is only 150 points." ”

High school math, the sudden f(x) gave the self-confident twin beauties a slap in the face.

"Obviously there is y and x, why is it f(x)! Sick of it! ”

While listening, Qingyun held back a smile.

This f(x), in fact, is the first difficulty that many students encounter after entering high school.

Because the textbook is not clear at all, it seems to appear out of thin air, and at this time it all depends on the level of the teacher.

Unfortunately, many teachers don't understand the fundamentals, or don't realize it, and that's the first problem that makes functions seem confusing.

And Qin Shiwan and Qin Shiyue are studying and previewing on their own, so they naturally see it in the clouds.

Qingyun smiled and asked the two of them to take out a pen and paper, "Don't worry, listen to me, I can explain it to you in a few minutes." Rest assured, it's not difficult to understand at all. ”

With that, he asked the two girls to write an equation on a piece of paper.

"The first point of the opening sentence, 'function equals rule', you have engraved these six words in my mind.

All functions are about the rules of their expression.

For example, the function y=f(x)=2x+3 means 'give an x, according to what rule to get a y, the rule is to multiply x by 2 and then add 3 to the result', can you understand this sentence? ”

The two little beauties thought for a while and nodded, and after Qingyun confirmed that they understood, she continued, "You see, f, is the code name of the rule, f(x) means to deal with x under the rules represented by f, you see, the small parentheses firmly frame x, which is not allowed x to escape its control."

y=f(x) means that the result of the processing is given to y.

Now, to understand this, y=f(x)=2x^2-5x+7.

If there is only the first half y=f(x), we only know that we need to calculate x under some kind of rule, but we don't know how to calculate it, with the second half, we know what the rule is. What is it? ”

The twin beauties nodded obediently and replied in unison, "According to the known rules, give me an x to calculate a result, and then let y equal this result." ”

Therefore, we use f(x) to represent any function, anyway, it is a function, and the specific rules have not been written for the time being, y=f(x), which is nothing more than the result of this function, which is represented by y.

So what about m=(t)? ”

"It means that t is calculated under some rule, and the result of the operation is given to m, do you understand the essence? In fact, they are all paper tigers. ”

Qin Shiwan pouted when she heard this, but Qin Shiyue pursed her lips, "Brother-in-law, what you said is light, I am now discovering more and more that mathematics is that you can understand concepts as soon as you talk about them, and you won't be able to do problems at a glance." ”

Qingyun shrugged his shoulders, "That is, you haven't learned the concept at all. ”

Looking at the two little beauties with teeth and claws, Qingyun smiled, "Then let me ask you, what is a function?" What is Letter? Why is it called a letter? ”

Qin Shiwan was about to endorse it, but was completely overwhelmed by the two questions behind Qingyun.

"Let me tell you my opinion, the letter is the meaning of the box, this box is like a TV, the input model has been processed, and the result is the picture, between the signal and the picture, the internal is the established operating rules......"

"NND, no teacher told me this back then, if I met a teacher like you, I would have been able to pass the Qingbei exam!" Qin Xiangyu, who slipped out quietly, was originally listening secretly beside him, and suddenly sighed.

Qingyun smiled and handed a cigarette to the brother-in-law, "The symbol like f(x) is too natural for the textbook writer and the teacher who is familiar with the function, as if 1+1 is equal to 2, it doesn't need to be explained and is not easy to explain, but for students who have just entered high school, it is a different experience."

Therefore, in fact, it is our current education, not only schools, but also the methods and methods of education that have gone wrong, and the people who teach are too taken for granted, and those who learn naturally can't listen to them.

The importance of empathy in education and teaching is to figure out what something is given to the student, not just to focus on what it is. ”

Qin Xiangyu didn't say anything yet, and Qin Tianshan, who came out to smoke and cared about the study of the baby girls, suddenly stopped.

Qin Tiansheng, who came out with him, looked at Qingyun in the courtyard with a strange expression, "Xiaoqing, you have something to say." ”

Obviously, this kid must have seen them, and when they walked out of the living room, this kid's voice was obviously a little louder.

Qingyun laughed twice, "Third uncle, if you don't dislike it, let Brother Xiangyu help me." ”

Qin Tiansheng was stunned for a moment, and then laughed with relief, "If you don't dislike your brother Xiangyu, you can take it to teach." ”

(End of chapter)