Sheep fight (hit a mathematical noun)
Answer: The vertex angle is opposite.
3. Much the same (type a mathematical noun).
Answer: similar.
This brain is really smart, blinking, carrying it all around, and it is not difficult to add, subtract, multiply and divide (as a calculation tool).
Answer: Calculator
5. Forge accounts (type a mathematical term)
Answer: False (Hypothesis)
6. The doctor raised his pen (typed a mathematical noun)
Answer: prescription
7. The queue is long, with a head and no tail. The "."is followed by a bar with the same appearance (guess a game).
Answer: Infinitely cyclic decimal
(2)
1, one plus one is not two. (Type a word)
A: Wang
2. One minus one is not zero. (Type a word)
Answer: Three.
3. Seven eighths. (Type an idiom)
Answer: Seven ups and eight downs.
The story of Zu Chongzhi.
Zu Chongzhi (AD 429-500) was born in Laiyuan County, Hebei Province during the Northern and Southern Dynasties. He read many books on astronomy and mathematics since childhood, studied hard and practiced hard, and finally made him an outstanding mathematician and astronomer in ancient China.
Zu Chongzhi's outstanding achievement in mathematics is about the calculation of pi. Before the Qin and Han Dynasties, people took "diameter of one week and three weeks" as π, which was called "ancient rate". Later, it was found that the error of ancient rate was too big, and pi should be "the diameter of the circle is one and greater than Wednesday", but there are different opinions on how much is left. Until the Three Kingdoms period, Liu Hui put forward a scientific method to calculate pi-"secant method", that is, to approximate the circumference of a circle with the circumference of inscribed regular polygons. Liu Hui calculated a polygon with 96 sides inscribed in a circle and got π=3. 14, and pointed out that the more sides inscribed in a regular polygon, the more accurate the π value obtained. On the basis of predecessors' achievements, Zu Chongzhi worked hard and calculated repeatedly, and found that π was between 3. 14 15926 and 3. 14 15927. The approximate value in the form of π fraction is obtained as the reduction rate and density rate, where the six decimal places are 3. 14 1929, which is the closest fraction to π value in 1000. How did Zu Chongzhi achieve this result? There's no way to check now. If you imagine that he will solve the problem according to Liu Hui's secant method, you must work out 16384 polygons inscribed in the circle. How much time and labor it takes! This shows that his perseverance and intelligence in academic research are admirable. It has been more than 1000 years since Zu Chongzhi calculated the secret rate and foreign mathematicians got the same result. In order to commemorate Zu Chongzhi's outstanding contribution, some foreign mathematicians suggested that π = be called "ancestral rate".
Zu Chongzhi exhibited famous works at that time and insisted on seeking truth from facts. He compared and analyzed a large number of materials calculated by himself, found serious mistakes in the past calendars, and dared to improve them. At the age of 33, he successfully compiled the Daming Calendar, which opened a new era in calendar history.
Zu Chongzhi and his son Zuxuan (also a famous mathematician in China) solved the calculation of the volume of a sphere with ingenious methods. One principle they adopted at that time was: "If the power supply potential is the same, the products cannot be different." That is to say, two solids located between two parallel planes are cut by any plane parallel to these two planes. If the areas of two sections are always equal, then the volumes of two solids are equal. This principle is called cavalieri principle in western languages, but it was discovered by Karl Marx more than 1000 years after the ancestor. In order to commemorate the great contribution of grandfather and son in discovering this principle, everyone also called this principle "the ancestor principle".
The story of gauss
Gauss has many interesting stories, and the first-hand information of these stories often comes from Gauss himself, because he always likes to talk about his childhood in his later years. We may doubt the truth of these stories, but many people have confirmed what he said.
Gauss's father works as a foreman in a tile factory. He always pays his workers every Saturday. When Gauss was three years old in the summer, when he was about to get paid, Little Gauss stood up and said, "Dad, you are mistaken." Then he said another number. It turned out that three-year-old Gauss was lying on the floor, secretly following his father to calculate who to pay. The results of recalculation proved that little Gauss was right, which made the adults standing there dumbfounded.
Gauss often said with a smile that he had learned to calculate before he learned to speak, and he often said that he learned to read by himself after asking adults how to pronounce letters.
At the age of seven, Goss entered St. Catherine's Primary School. When I was about ten years old, my teacher had a problem in arithmetic class: write down the integers from 1 to 100, and then add them up! Whenever there is an exam, they have this habit: the first person who finishes it puts the slate face down on the teacher's desk, and the second person puts the slate on the first slate, thus falling one by one. Of course, this question is not difficult for people who have studied arithmetic progression, but these children are just beginning to learn arithmetic! The teacher thinks he can have a rest. But he was wrong, because in less than a few seconds, Gauss had put the slate on the lecture table and said, "Here is the answer!" " "Other students add up the numbers one by one, and sweat on their foreheads, but Gauss sat quietly, ignoring the contempt and suspicious eyes from the teacher. After the exam, the teacher checked the slate one by one. Most of them were wrong, so the students were whipped. Finally, Gauss's slate was turned over and there was only one number on it: 5050 (needless to say, this is the correct answer. The teacher was taken aback, and Gauss explained how he found the answer:1+100 =1,2+99 =10/,3+98 =/kloc-. 0 1=5050。 It can be seen that Gauss found the symmetry of arithmetic progression, and then put the numbers together in pairs, just like the general arithmetic progression summation process.
A Self-taught Mathematician —— The Story of Hua
Mathematician Hua dropped out of school when he was a teenager and helped his father run a small cotton shop. In his spare time, he often solves math problems with paper wrapped in cotton.
One day, his father asked him to clean the back room. After cleaning, he went back to the counter and cried, "Where is my arithmetic draft paper?" Dad looked around. Suddenly, he pointed to the back of a person in the distance and said, "I sold my cotton bag to him." Hua caught up with him, bowed, took out his pen and copied the topic on the back of his hand. Passers-by said, "This is really a strange child." Sometimes customers come to buy things, and people ask questions and answer them, which delays business. In the evening, when the shop was closed, he taught himself until late at night. Seeing that he didn't focus on business, his father snatched the book from his hand in a rage and wanted to put it in the stove. It's a good thing his mother got it and it didn't burn.
Once, Hua read a magazine and found that a math paper was wrong. Encouraged by his teacher, he wrote a critical paper and sent it to Shanghai Science Journal, which was published soon. This article changed his path and led him to the palace of mathematics.
Interesting problems in mathematics
1. There are five girls sitting side by side in the subway car. A sits at exactly the same distance from B and C, D sits at exactly the same distance from A and C, and E sits between her relatives and friends. Who are E's relatives and friends?
Answer: E sits between A and B, and A and B are her relatives and friends.
There are 692 infantry in a fortress. Every four people stand in a horizontal row, walk forward at intervals of 1 meter 1, and walk 86 meters per minute. Now we must cross this 86-meter-long bridge. How many minutes does it take from the first row to the last row?
Answer: 3 minutes.
3. A farmer keeps 9 sheep, 7 pigs and 5 cows. In terms of price, two sheep can be exchanged for a pig, and five sheep can be exchanged for 1 cow. He wants to give these cows, sheep and pigs to his three sons. Not only will no one get the same number of livestock, but their value will be the same. Can you come up with a distribution plan?
Answer: the eldest son points 1 cow, 5 pigs, 1 sheep; The second son is divided into 2 cows, 1 pig and 4 sheep; The third son is divided into 2 cows, 1 pig and 4 sheep.
4. Distance between two cars 1500m. Suppose the front car is driving at a speed of 90km/h and the rear car is chasing at a speed of 144km/h, how far apart are the two cars in one second when they collide?
Answer: Distance15m.
There are two companies, A and B, recruiting managers. The annual salary of a company is 6,543,800 yuan, and the salary is raised once a year, with a salary increase of 20,000 yuan each time; Company B has a salary of 50,000 for half a year, with a salary increase of 5,000 for half a year. Which company pays more?
Answer: Go to Company B to earn more money.
6. The famous Russian mathematician lomonosov borrowed the book Mathematical Principles from his neighbor. The neighbor said to him, "You help me chop wood 10 days, and I will give you the book and give you 20 rubles." As a result, he only chopped firewood for seven days. After the neighbor gave him the book, he paid another 5 rubles. What is the price of the book Principles of Mathematics?
A: The price of this book is 30 rubles.
7. The bottle contains1000g of alcohol with the concentration of 15%. Now pour 100 grams of 400 grams of alcohol A and B into the bottle, and the concentration of alcohol in the bottle becomes 14%. It is known that the concentration of alcohol A is twice that of alcohol B. How to find the concentration of alcohol A?