Super Xueba: Start With A Low Control Score!

Chapter 246 The best solution, there is no fastest, only faster!

This is Qin Yumo’s answer, just because she made it first, she took her answer as the first point of view.

In fact…

The answers of Su Yu, Zhang Hao and Li Qianqian are exactly the same as Qin Yumo’s, and they are not much different.

As for Huang Sihai, needless to say, with his scum strength, naturally he couldn’t solve this problem.

As the five people walked off the podium, they returned to their positions.

Jiang Nan’s gaze swept across the square, “Okay, now everyone has done it, and all the people on the podium have done it. Let’s take a look at the first question first. Do you all think it is correct?”

“…”

“correct!”

The people underneath said in unison.

Even including the teacher Hu Yifei.

Although Hu Yifei has fallen behind in mathematics in the past few years, his vision is here after all, and he knows that there is no problem at the first glance.

As for other things like Huang Sihai and Hu Dajun, you may not understand it, but Jiang Nan’s answer was made by monitor Qin Yumo, and Su Yu, Zhang Hao and Li Qianqian had basically the same answers. It must be correct!

“Um!”

“You are right!”

“This answer is indeed correct.”

Jiang Nan nodded, but immediately shook his head: “But I also said before. Whether you don’t do homework or want to rest after class, you need to make the best solution, that is, the process is optimized. !”

“Then I will ask again, do you think the problem-solving process on the blackboard has been optimized?”

“Or maybe…”

“Do you have any better ideas for solving problems?”

“…”

“There are no other ideas for solving problems!”

“It should be optimized!”

“After all, this was done by squad leader Qin Yumo, so did Su Yu, Zhang Hao, and Li Qianqian. It must be very good already!”

“I think the idea of ​​solving the problem is very clear!”

“Originally I didn’t make it, but now it suddenly dawns on me that if I encounter it next time, I will do it too!”

“That’s right, I also gave up my studies!”

“Squad leader bullfrog!”

“The math class represents the bullfrog!”

“The physics class represents the bullfrog!”

“The study committee is also a bullfrog!”

“…”

Everyone praised Qin Yumo.

certainly!

They are indeed worthy of praise.

after all……

The love curve question on the blackboard is very simple for Jiang Nan, but there are not many that can be done there.

It can be seen from this.

Qin Yumo, these tyrants, are still very powerful.

However, Jiang Nan curled his lips at this, looking helplessly at Qin Yumo and Su Yu, “You think about it again, are you sure there is no other better way to solve the problem?”

“…”

“No!”

“Really gone!”

“Even if I want to break my head, I only have this!”

Su Yu, Zhang Hao and Li Qianqian shook their heads at the same time.

Even Qin Yumo is like this.

But the next second.

Qin Yumo looked at Jiang Nan hesitantly again, “Ms. Jiang Nan, you… do you have a better idea?”

“…”

“Please delete the word [?]!”

Jiang Nan curled his lips: “Of course, I don’t want to hit you either. Your foundation is still good.”

“At least most of them have made this question.”

“but……”

“Your thinking is limited and not open enough. Although the problem-solving ideas are correct, they are too modest.”

“According to your solution, if it is encountered in the exam, it will take at least ten minutes. How long will it be delayed? Do you still need to do the following questions?”

“When we take the exam, we must not only be right, but also be fast, so we must find the optimal solution.”

“And the question above.”

“I can find three or five solutions just by thinking about it.”

“And each one can greatly reduce time.”

“…”

Finished!

Jiang Nan wiped Su Yu’s answer on the blackboard, and then quickly wrote “swish”.

Solution one…

Start with the conclusions “not more than” and “less than”, use basic inequalities to scale, and then use graphics to estimate the area.

Because x^2+y^2=1+|x|y≤1+|x|y≤(x^2+y^2)/2.

So x^2+y^2≤2.

1: The possible integer value of x is soil 1, 0, and substituting into the equation of curve C, the coordinates of the whole point are (1,1)(1,0)(-1,1)(-1,0)…so the serial number 1 is correct.

2: Let the distance from any point on the curve C to the origin be d, then d=x^2+y^2≤2.

So d≤√2.

Therefore, the serial number 2 is correct.

3: The area S of the graph in the first quadrant is greater than 1, and the area S of the graph in the fourth quadrant is greater than 1/2. From the symmetry, the area S of the “heart-shaped” district is greater than (1+1/2)x2=3 .

Therefore, the serial number 3 is wrong.

In summary, we can see that C is selected.

…

Thirty seconds.

It’s not even thirty seconds.

Jiang Nan wrote a new solution.

And this new solution was many times simpler than the solution of Qin Yumo and others just now.

There is no coordinate equation, and there is no need to build a coordinate system, but only need to grasp “not more than” and “less than”.

If it takes more than ten minutes for Qin Yumo’s solution to be done by the people present, then Jiang Nan’s solution can be done in five minutes (including examination and thinking time).

Gee!

The two are in contrast to each other.

“this……”

“How is it possible, how could this be?”

“Why is Nanshen’s solution so simple and quick?”

“Don’t talk about high school students, even junior high school students, after reading Teacher Jiang Nan’s solution, they can understand it in seconds!”

“It can be said……”

“This is not a high school solution at all!”

“And used junior high school knowledge.”

“But why…”

“I just couldn’t think of it?”

“…”

There is one child’s shoe in the class, and they are all dumbfounded, including the head teacher Hu Yifei.

This is really incredible.

In other words…

Jiang Nan’s solution is not only simple, but also easy to understand. Even Huang Sihai and Hu Dajun can understand and learn it instantly.

but……

What surprised them was not only that.

I saw Jiang Nan erased Zhang Hao’s solution again, and wrote quickly again.

“and many more!”

“Ms. Jiang Nan, what are you…”

The students present wanted to ask subconsciously, but they stopped abruptly because Jiang Nan had finished writing.

The second solution.

That is Jiang Nan’s second solution.

And this solution is faster than the first solution just now, simpler and clearer, and more familiar.

how to say?

It is to use the mathematics knowledge learned in the fifth and sixth grades of elementary school to easily make this third grade question.

Gee!

It can only be described in one word.

That is, absolutely.

“Fighting into a horse, terrifying!”

“The bullfrog is so spicy!”

“Nan Shen is worthy of being a Southern God, it’s amazing!”

“…”

Everyone in the class, including Hu Yifei, the head teacher, had their eyes widened and surprised to the extreme.

However, I read few books, and I’m in the world.

They really couldn’t find other words to describe their mood at the moment, only to pinch their thighs violently over and over again.

And at this moment.

Jiang Nan wiped out Li Qianqian’s solution again, and wrote it quickly again, and at the same time said: “The two solutions just now took much shorter time than yours, but they were in the college entrance examination. It’s still far from fast enough.”

“Because this is a multiple-choice question, we don’t need to make it so complicated at all.”

“As long as you use the reverse method, you can do it easily.”

“…”

The voice fell off.

Jiang Nan’s problem-solving process came out.

Hu Yifei: “%￥#@#￥%……”

Qin Yumo: “%￥#@#￥%……”

Su Yu Zhang Hao Li Qianqian: “%￥#@#￥%……”

They all opened their mouths wide, surprised to the extreme.

However……

“Of course, if you still think it takes too much time, I still have a faster method, which is the special value substitution method!”

Jiang Nan continued to write as he spoke.

“%￥#@#￥%……”

Everyone had a numb scalp and was completely blinded.

Damn!

Damn!

Damn hastily!

No other words can be said, but I can only hold onto this legendary plant and stuff it in my stomach!

…

sp: The content of this chapter is purely fictitious. Any similarity is purely coincidental. Please do not substitute into reality. Thank you for your support!