Back home, Yi Cheng observed the state of the goddess.

Goddess Type: [Goddess of Water]

Name: [Blue Ice]

Current level: Lv2, Primordial Stage

Hunger: 32

Fatigue value: 34

Opinion: 60

Very good, the favorability has not decreased.

Yi Cheng finally put his mind at ease.

"You wait a little longer, I'll cook."

It's already 10:20 p.m., and it's past the normal meal time.

It's weird.

Lan Bing thought to himself.

Why is it the same dream again?

Can Freud explain how serial dreams come about?

Once raw and twice ripe, she is now used to it.

Lan Bing lazily lay on the edge of the basin, for some reason, without much hunger.

For the school anniversary in two days, she has been practicing the violin desperately for the past two days, only to feel that her neck is sore and her fingers are sore to death.

By the way, speaking of school anniversaries......

She looked up at Yi Cheng, who was sleeping on the bed.

Didn't you say you'd go cook for me? Why did you run to sleep?!

After half an hour, Yi Cheng sat up from the bed.

This guy was like a trick and didn't know where to touch a fish out.

The fish was very peculiar, about twenty centimeters long, with a large head that occupied about half of the body, and the whole body was divided into seven horizontal stripes, which were red, orange, yellow, green, blue, and purple.

This is the Lv2 level Colorful Fish unlocked in the previous system.

Now feeding the goddess level 1 dream fruit can't increase much experience and hunger points.

Speaking of hunger, I have to say that I have to complain about the breadth and profundity of Chinese characters.

Hunger value, high means that hunger is satisfied, so not hungry, low is hungry;

But it can also be understood the other way around, a high hunger is very hungry, and a low hunger is not very hungry.

It's like a tram, oh no, like a wolf's white strip.

If you don't hit the iron for a few hours, you don't understand that it's for nothing to get full.

Catching the Colorful Fish of Lv2 is not at all comparable to the difficulty of the Dream Fruit of Lv1.

The colorful fish is a creature that lurks in the small stream of the dream, and the current is very fast, plus the little guy's swimming speed is super fast, and the body swing is extremely flexible, which makes Yi Cheng try his best, and it took an hour and a half in the dream to barely catch such one.

The lv2 swimming skill combined with the lv1 diving skill allows Yi Cheng to swim and steer freely like a fish in the water.

If someone was on hand to calculate his speed swim score, he would be taken aback.

Now Yicheng's swimming speed has exceeded the normal level of national first-class athletes.

But you would be naïve to think that you can catch fish in a stream with your bare hands at the level of a national first-class athlete.

Yi Cheng relied on blocking the ends of the river with stones, leaving only a slightly wider slit as a trap.

Then he drove it into the net pocket in a circle, and then caught it.

[Successfully caught a colorful fish.]

Reward: Dream Fishing Rod x1. 】

the chicken.

Give this kind of thing early!

Yi Cheng rolled his eyes helplessly in his heart.

He put on his apron, walked into the kitchen, and began to cook food for Blue Ice.

The better and fresher the ingredients, the easier the cooking method will be.

According to the Cantonese way of making fish (no need to guess, the author is not Cantonese), you only need to put shredded ginger and garlic cloves in the mouth of the fish as a seasoning to remove the fish.

After that, as long as it is steamed and lightly salted, the flavor of the fish can be preserved to the maximum.

It's not that sliced fish, barrel fish, hob, chopped pepper fish, spicy fish, boiled fish, pork rib fish, pork bone fish, jumping frog fish, golden sauce fish, surf fish...... The sour soup fish is not good enough, but Yi Cheng feels that for the first time, he should use this simple way to truly judge whether the meat of the fish itself is delicious enough.

After a few minutes, Yi Cheng put the steamed colorful fish in front of the goddess.

Lan Bing had long been dressed and sat on the dining table with his legs sideways.

"Wow, it smells so good."

Lan Bing fanned his hand in front of his nose.

Speaking of which, if this thing exists in reality, it can definitely be regarded as a famous dish.

Don't look at the colorful fish, it is not big, and it is only about ten centimeters after removing the head and tail, but the meat is extremely delicious, far better than all the fish she eats.

You must know that with her family background, she has not eaten expensive meals.

Even a three-star Michelin restaurant in France, she has eaten it.

But that taste really doesn't compare to what it does now.

It's going to......

What if you can't eat such delicious food again?

Yi Cheng handed her a pair of toy chopsticks (a whole set of Barbie toys given by a reader during the autograph session of American book friends before. Then I picked up the chopsticks and tasted a small bite.

"Hmmm......"

The two of them clamped together......

"That's pretty good."

Yi Cheng admired.

In less than 5 minutes, there was a pile of fish bones left on the plate.

Ku Ding has never been so meticulous.

Yi Cheng slammed his mouth unfinished, he only tasted two bites, and gave the rest to Lan Bing.

It is easy to go from thrift to luxury, and it is difficult to go from luxury to thrift.

He couldn't let food stop him from learning.

Lan Bing leaned back on the sofa with satisfaction, watched Yi Cheng take out the private goods card given by Teacher Ran today, and began to work on the question.

She glanced at it hurriedly.

Obviously, there is much more text narrative today than yesterday's, and the first and second pages of the A6 paper are densely written.

Yicheng examines the question from scratch:

(1) In the unary quadratic equation ax^2+bx+c=0 (a≠0 and △=b^2-4ac greater than 0), let the two roots be x1 and x2 (I don't know why, I can't play the greater than sign at the starting point)

Test Proof:

x1+x2=-b/a

x1·x2=c/a

1/x1+1/x2=（x1+x2）/x1·x2

(Note: It is not allowed to be proved by the root finding formula of a quadratic equation)

Hey, it's pretty simple.

Yi Cheng thought to himself, isn't this a junior high school topic?

"Vedic theorem." Lan Bing next to him sighed.

"Well, yes." Yi Cheng nodded in response.

This is the very famous Vedic theorem in the history of mathematics.

It is not an exaggeration to say that it is a great theorem, which for the first time expounds the relationship between roots and coefficients.

As early as the 21st century B.C., the ancient Babylonians gave a formula for finding the roots of a quadratic equation with the first term 1.

Yes, Yi Cheng, who was still in the sixth grade of elementary school at the time, was completely shocked when he learned about this.

To this day, there are still more than hundreds of millions of Chinese people who cannot solve the one-dimensional quadratic equation, which has been recorded more than 4,000 years ago.

The tablet containing the famous algorithm is known as the Britannia 13901 Clay Tablet and is now in the British Museum.

Icheng has always wanted to visit the British Museum to see this amazing stone slab.

Even once.

The one-dimensional quadratic equation algorithm, which was discovered in the 21st century BC, was not discovered until the 16th century by the French mathematician Veda in which the relationship between roots and coefficients was discovered.

and left behind the miraculous Vedic theorem for posterity.

The inheritance of history is so wonderful, it took 3,700 years to discover the inner relationship, and the proof of Vedda's theorem waited 200 years for Gauss, the prince of mathematics, to prove the fundamental theorem of algebra before it was fully proved.

"Another formula related to Gauss." Yi Cheng smiled.

Fortunately, he is still a high school student, so he doesn't need to prove the fundamental theorems of algebra like Gauss, as long as he uses it.

The only trouble is that the article says that you can't use the root finding formula directly.

But it doesn't matter.

Yi Cheng smiled slightly.

I just need to re-deduce the root finding formula, which is a derivation process that can be easily completed by junior high school students.