Chen Xu smiled: "I can teach you two methods, the first is the lazy method, and the second is the regular method, I don't know if you want to learn?" ”

Kong Yingda asked, "Does that include calculations?" ”

Chen Xu shook his head: "Not including the calculation chips, if you use the calculation chips, you will definitely be able to calculate them." ”

Everyone was shocked, there are actually two ways to do it without calculation, which ......

Li Chengqian and others were also in awe, and hurriedly surrendered their hands to the teacher and invited Professor Chen Xu.

"Let's take a look at the lazy man's solution first." Li Er asked seemingly seriously, but in fact, he had a heart in his heart that wanted to be lazy, this two-digit algorithm, he usually used it occasionally when he counted soldiers and food.

Chen Xu motioned for everyone to come around, there was a piece of sand in front of him, he held a branch in his hand, and wrote two thirty-nine side by side on the sand.

"You see, when these two numbers are multiplied, do they end up with three digits?"

Kong Yingda stroked his beard and nodded, this is inevitable.

Subsequently, Chen Xu taught a popular method of abXcd=ac+(ad+bc)+bd.

The trick of this method is to calculate the results of 100 digits separately and add them up together, so that only a piece of sand and a tree branch are needed to calculate.

If you use it well, you can also calculate it directly, which can be said to be a very funny and simple way to be lazy.

Because Chen Xu taught it hand-in-hand, people like Kong Yingda, Changsun Wuji and others were all talented and intelligent, and they learned it immediately, and they also made up a number to calculate, and finally used the calculation chip to check.

I found that the final answers were all correct, and I couldn't help but admire it.

Chen Xu waved his hand: "Where is this, don't panic, there is still room for further improvement in this calculation method in the future, but let's talk about it then." ”

Chen Xu is talking about turning Chinese characters into Arabic numerals, otherwise it is simply exhausting to always use Chinese characters to express numbers.

"The regular algorithm is like this, which is more similar to the algorithm just now, but the idea of calculation is different."

Chen Xu taught the formal method of double-digit calculation again, and everyone nodded to remember it, and praised Chen Xu's knowledge.

"Okay, you can discuss your affairs, and I'll teach Li Chengqian to further become proficient in the calculation of numbers."

Chen Xu smiled, took the three of them to the backyard, and began to give them calculation problems.

This calculation problem that made the students miserable in later generations was very novel in Datang at this time, at least Li Chengqian and others could be freed from the unfinished book, and they were also excited.

And Chen Xu didn't have many questions, the three of them were giggling, playing while doing it, and Chen Xu didn't care about them, which made the three of them feel very good, and the time passed quickly.

In the evening, as usual, Li Er invited him to stay for dinner, and the eldest grandson Wuji and others asked him if he had more skin care soap.

After all, this thing is really easy to use, but yesterday Chen Xu only brought one box, and Li Er almost took all of it to Li Yuan, and they couldn't enjoy it.

Knowing its benefits, who is not greedy, everyone is greedy.

Chen Xu said: "It's actually no problem to give it to you, but you must pay attention to it, this thing can't be taken out to show off." ”

"Now we rely on this thing to control these harem concubines, if you take out the soap to show off, give them the illusion that this thing is all over the street, then the effect of controlling them will be weakened."

Chen Xu said to everyone, a group of people nodded again and again, and Li Er also glanced at Chen Xu appreciatively.

Chen Shi is Chen Shi, and he is too thoughtful about things!

These concubines just keep adding trouble to him, if they find that the value of soap is not as high as they imagined, not only they have it, it is estimated that they will have to make some moths at that time.

It's good to be able to maintain the current situation, if they don't find trouble for themselves, they will have a lot less opportunities to blow the wind on their father's pillow, so that their situation will be better, and they can slowly figure it out.

Everyone said that there was absolutely no problem, they couldn't hide this kind of treasure, and they would never take it out.

Cheng Yanjin smiled: "When I go to court tomorrow, my old Cheng will have bright skin, and I can't look at those who call me Cheng Heizi every day!" ”

Chen Xu couldn't laugh or cry, this thing is descaling, and long-term use can make the skin whiter, so forget it.

After agreeing to send a guard to go back with him later in the evening, Chen Xu talked about eating again.

"Alas, Your Highness, to be honest, it's not that I don't want to stay and eat, it's just that I don't think Datang's food is really delicious enough."

Chen Xu complained that the Chinese diet did not begin to gradually improve until the Ming Dynasty, many seasonings and foods were available, and the cooking technology was also mature.

In the Tang Dynasty, stir-frying was not invented, and there were many types of vegetables and not enough seasonings, which made him eat it, which was terrible.

All day long, it is steaming, boiling, or the kind of low salt and less taste, Chen Xu cried when he ate it.

Li Er immediately asked, "Then Master Chen doesn't know if there are any suggestions for improvement?" ”

Li Er is also very good, my Datang food is not good, it doesn't matter, there is Master Chen, you give us a lesson and see what to do, then we can also enjoy the mouth?

"Alas, you should first learn the cooking method of stir-frying, although the gentleman is far away from cooking, but you should have fun, now go and call the cooks in the kitchen."

As soon as Chen Xu gave the order, the cooks of the Qin Palace's Mansion naturally gathered obediently.

Chen Xu asked them to find an iron pot, but Datang did not have an iron pot...... After all, there's no way to stir-fry, where did this thing come from?

But this is not difficult for the talents of the Qin Palace, and soon the two blacksmiths directly built it themselves according to Chen Xu's requirements, which is very hardcore.

After the pot was cleaned up, Chen Xu asked people to fetch sesame oil and taught a simple and practical method of stir-frying.

With the escape of the aroma of oil, in the violent cooking sound, the dishes were tumbling inside, and the spices of the Tang people such as salt were sprinkled into it, although these things were very lacking, but it still made the whole iron pot exude a terrible fragrance.

"This ......"

Kong Yingda, Changsun Wuji and others were dumbfounded, no one thought that there would be such a cooking method!

It looks so simple, almost after seeing it, as long as you build an iron pot, shovel and other tools, every household, at least every household standing here, can buy it.

After the cabbage and tofu were fried, Chen Xu put the dishes on the plate, tasted the taste first, nodded, the taste was still poor, but compared to the dark cuisine of Datang at this time, it was much better.

Seeing that Master Chen asked them to taste it, Li Erer didn't say a word, picked up the chopsticks and hurried to try it first.

A completely unusual taste of the dish, a more refreshing and appetizing taste...... Damn, Li Er suddenly fell in love with this way of eating.