![](data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" viewBox="0 0 72 71" width="72"></svg>)
Zuchongzhi also wrote a book called‘
Zuchongzhi (429-500 A.D.) was a native of Laiyuan County, Hebei Province during the southern and Northern Dynasties. He read many books on astronomy and mathematics since he was a child. He was diligent in learning and practising hard. He finally became an outstanding mathematician and astronomer in ancient China. His outstanding achievement in mathematics is about the calculation of PI
What is the contribution of Zu Chongzhi
Zu Chongzhi (April 20, 429 - ad 500) is an outstanding mathematician and scientist in China. His main contributions are mathematics, astronomy, calendar and mechanics
Zu Chongzhi, for the first time in the history of mathematics in the world, calculated the value of pi to six decimal places, that is, between 3.1415926 and 3.1415927. He put forward about 22 / 7 and 355 / 113, which was the first time in the world, 1100 years earlier than that in Europe. Therefore, it is advocated to call it "Zulu", that is, the ancestor of PI
He is not only an outstanding mathematician and astronomer, but also an outstanding mechanical expert. He has rebuilt many kinds of ingenious machines, such as guidecar, Qianli boat, water hammer mill, which have been lost for a long time
After years of calculation, he compiled a new calendar, Daming calendar, which was the most advanced calendar in the world at that time
What is nine chapter arithmetic and how much is it?
Nine chapters arithmetic is the first mathematical monograph in ancient China. It is one of the most important books in the ten books of Suan Jing. It is rich in content and systematically summarizes the mathematical achievements in the Warring States, Qin and Han Dynasties
As shown in the figure, in △ ABC and △ BCD, ab = AC = 4, BD intersects AC at point E, AE = 3, and ∠ BAC = 2 ∠ BDC=______ .
∵AB=AC=4，AE=3，
∴CE=1，
∵∠BAC=2∠BDC，
The points B, C and D are on the circle with point a as the center and ab as the radius,
According to the intersecting string theorem, be · ed = CE · (AE + AB) is obtained,
∴BE•ED=1×（3+4）=7．
So the answer is: 7
Chapter 8, topic 5, arithmetic in nine chapters
If the unit prices of cattle, sheep and pigs are x, y and Z, then the equations can be formulated as follows: 2x + 5Y = 13z + 1000 (the money for selling 2 cattle and 5 sheep is equal to buying 13 pigs plus the remaining money) 3x + 3Z = 9y (the money for selling 3 cattle and 3 pigs is equal to the money for buying 9 sheep) 6y + 8Z = 5x-600
No matter big circle or small circle, the circumference of a circle is always 3.14 times its diameter______ .
From the analysis, we know that the circumference of a circle is always π times of its diameter no matter whether it is a big circle or a small circle
The answer is
The circumference of a circle is enlarged by three times, its half diameter is enlarged by times, and its area is enlarged by times
The circumference of a circle is enlarged by three times, its half diameter is enlarged by times, and its area is enlarged by times
Answer: the circumference of the circle C = 2 Π R
Area of circle s = π R ^ 2
Therefore, if the circumference is expanded by three times, the radius, diameter and area will be expanded by three times and nine times respectively
Estimate the circumference of a circle with a diameter of 8 cm by using "Wednesday diameter 1"
8x3 = 24cm
The circumference of a circle is 3.14 times of its diameter
C=2πr=πd
No, because π is an irrational number, and its value is not equal to 3.14
The circumference of a circle is () times of its diameter; its circumference is about () times of its diameter; its circumference is more than () of its diameter
The circumference of a circle is (π) times of its diameter; its circumference is about (3.14) times of its diameter; its circumference is (3) more than its diameter
RELATED INFORMATIONS
- 1. Find some English stories. Do me a favor. On Wednesday, I have to Hope is some fairy tales in English
- 2. What do you mean by listening? Be simple and clear! Use it in primary school science
- 3. Find 20 Pythagorean theorem to solve more problems!
- 4. The problem of calculating the area of double knobs by integral It seems that θ can't take pi / 4 to pi / 2? When drawing, is the graph in the first quadrant only 0 to pi / 4? So when integrating in polar coordinates, the upper limit of integration is pi / 4, right? And I still don't know whether the angle in polar coordinates is determined by the angle between the X axis and the X axis, and the graphs with angles not in the defined domain will not be drawn Although it seems that the graph is continuous, its value of θ is not continuous, is it? Thank you!
- 5. The definition of Pythagorean theorem, specific
- 6. Chinese mathematicians Who knows? Easy!
- 7. There is a mathematical Pythagorean theorem problem It is known that there are two fishing boats in port B. ship a and ship b set out at the same time. If ship a goes along the direction of 60 degrees north by east at a speed of 8 nautical miles per hour, ship B sails along the direction of 30 degrees south by East with a speed of 9 nautical miles per hour. Two hours later, ship a arrives at Island m and ship B sails to island P. please estimate the distance between island m and island P
- 8. The earliest mathematical masterpiece in the world is "nine chapters on arithmetic". What is the earliest "origin of species" in the world?
- 9. Observe the number of the following columns in order of + 2, - 4, + 6, - 8, + 10. According to its sorting rule, the number of 2012 should be?
- 10. How do these numbers find the rule 1, 2, 4, 8, 16, 32 Up to 64, how much does it add up to? What is the rule formula?
- 11. Chapter nine arithmetic problems The water surface of a pool is 10 feet square. In the center, there is a reed which is one foot higher than the water surface. If you pull it vertically to the bank, its top just reaches the surface of the bank. Ask the water depth and the length of the reed
- 12. Why is Pythagorean theorem the first mathematical theorem discovered by human beings? When I studied the Pythagorean theorem, I felt that the discovery of this theorem was not simple. Why do many countries say that the Pythagorean theorem is the earliest mathematical theorem they know. Is this accidental or
- 13. Exploration on the expansion of 94 pages in the experimental textbook of compulsory education curriculum standard
- 14. Junior high school mathematics book Volume 1, page 24 exercise (in the inquiry below) 4 problem formula Plus answer!
- 15. 2005x－2007y＝2003 2004x－2006y＝2002 x. How much y
- 16. If the rational number a is greater than the rational number B, then () A. The absolute value of a is greater than that of B B. The absolute value of a is less than that of B C. The opposite number of a is greater than that of B D. The opposite number of a is less than that of B
- 17. The answer to the latest test paper of compulsory education curriculum standard experimental textbook published by people's Education Press I am a teacher, I want to let students read early at the end of the term!
- 18. The Beijing Tianjin Intercity Railway will be put into operation on August 1, 2008. It is estimated that the one-way direct operation time of high-speed train between Beijing and Tianjin will be half an hour. In a test run, the running time of the test train from Beijing to Tianjin is 6 minutes longer than the expected time, and the travel time from Tianjin to Beijing is the same as the expected time The average driving speed is 40 kilometers per hour. What is the average speed from Beijing to Tianjin during the test run?
- 19. On the number axis, an ant starts from the origin and crawls 1 unit length to the right for the first time, then 2 units to the left for the second time, 3 units to the right for the third time, and 4 units to the left for the fourth time, Question: (1) where is the last position of the ant on the number axis? (2) what is the sum of the numbers corresponding to the positions reached after each crawl? (3) how long has the ant crawled
- 20. 1.（10-11）×（11-12）×（12-13）×… ×（99-100）=_____ . 2. - 1 - (- 5 and 1 / 2) × (+ 3 / 11) [main process] 3.2 / 3 × (- 1 / 2) - (- 1 and 1 / 2) × (- 1 and 1 / 3) [main process] 4. Simple calculation: 15 × (- 3 / 5 + 1 / 3) - 24 × (5 / 12-7 / 8) [main process] 5. Using a simple method to calculate: - 8 × (- 13 and 7 / 12) - (- 5) × (- 13 and 7 / 12) + 4 × (- 13 and 7 / 12) [main process] 6. Two kinds of operations are defined as follows: + 0means "+ there is a circle outside" × "means" × there is a circle outside ". For any two rational numbers a, B has: a + ○ B = a + B-2, a ×0b = a · B-2. Find the value of - 4 × (6 + ○ 8)