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1. Liu Hui (born around 250 AD) is a very great mathematician in the history of Chinese mathematics and occupies a prominent position in the history of world mathematics. His representative works "Nine Arithmetic Notes" and "Arithmetic Classics on the Island" are the most precious mathematical heritages in China.

Nine Chapters of Arithmetic was written in the early Eastern Han Dynasty, with 246 solutions. It is advanced in the world in solving simultaneous equations, calculating four fractions, calculating positive and negative numbers, calculating the volume and area of geometric figures and many other aspects. However, due to the original solution, they lacked the necessary proof, and Liu Hui made supplementary proof. In these proofs, his creative contributions in many aspects are shown. He was the first person in the world to put forward the concept of decimal, and used decimal to represent the cube root of irrational numbers. In algebra, he correctly put forward the concept of positive and negative numbers and the rules of addition and subtraction; The solution of linear equations is improved. In geometry, "secant" is put forward, that is, the method of finding the area and perimeter of a circle by using inscribed or circumscribed regular polygons to exhaust the circumference. He scientifically obtained the result that pi = 3. 14 by using secant technology. Liu Hui's theory "carefully cut the circle and lose little;" Cut hard, can't cut, just into the circle, don't lose anything "can be regarded as the representative work of China's ancient limit concept.

In the book Island Calculation, Liu Hui carefully selected nine survey questions. The creativity, complexity and representativeness of these topics attracted the attention of the west at that time.

Liu Hui has quick thinking and flexible methods. He advocates reasoning and intuition. He was the first person in China who explicitly advocated using logical reasoning to demonstrate mathematical propositions.

Liu Hui's life is a life of hard exploration of mathematics. Although his position is low, his personality is noble. He is not a mediocre man who seeks fame and fame, but a great man who never tires of learning. He left us a valuable fortune.

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.

2. Zu Chongzhi's outstanding achievement in mathematics is about the calculation of pi. Before the Qin and Han Dynasties, people took "the diameter of three weeks a week" as pi, that is, "the 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 will not 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".

3. leonhard euler 1707- 1783 was born in Basel, Switzerland. 13 went to university of basel to study and got the most famous mathematician at that time (John johann bernoulli, 1667-.

Euler's profound knowledge, endless creative energy and unprecedented rich works are amazing! He began to publish papers at the age of 19, until he was 76 years old, and wrote a sea of books and papers for more than half a century. Today, Euler's name can be seen in almost every field of mathematics, from Euler line of elementary geometry, euler theorem of polyhedron, Euler transformation formula of solid analytic geometry, Euler solution of quartic equation to Euler function in number theory, Euler equation of differential equation, Euler constant of series theory, Euler equation of variational method, Euler formula of complex variable function and so on. His contribution to mathematical analysis is even more original. Introduction to infinitesimal analysis is his epoch-making masterpiece. At that time, mathematicians called him "the embodiment of analysis".

Euler is the most prolific outstanding mathematician in the history of science. According to statistics, * * * has written 886 books and papers in his tireless life, of which 40% is analysis, algebra and number theory, 18% is geometry, 28% is physics and mechanics, 1 1% is astronomy, as well as ballistics and navigation.

It is no accident that Euler's works are surprisingly numerous. He can work in any harsh environment. He often holds his children on his knees to finish his papers, regardless of their noise. His indomitable perseverance and tireless spirit of scholarship made him never stop studying mathematics after he became blind. During the 17 years after his blindness, he also dictated several books and about 400 papers. /kloc-Gauss (1777- 1855), a great mathematician in the 9th century, once said: "Studying Euler's works is always the best way to understand mathematics."

Euler's father Paul Euler is also a mathematician. He wants little Euler to study theology and teach him a little at the same time. Because of his talent and unusual diligence, little Euler got the appreciation and special guidance of johann bernoulli. When he was 19 years old, he wrote a paper on masts and won a prize from the Paris Academy of Sciences. His father no longer opposed him to study mathematics.

1725, johann bernoulli's son daniel bernoulli went to Russia and recommended Euler to czar Cadling I, so Euler came to Petersburg in May 1727. 1733, at the age of 26, Euler became a professor of mathematics at the Academy of Sciences in Petersburg. 1735, Euler solved an astronomical problem (calculating the orbit of a comet), which took several famous mathematicians several months to solve, but Euler used his own invented method and completed it in three days. However, overwork made him suffer from eye diseases and unfortunately lost his right eye. At this time, he was only 28 years old. 174 1 year, at the invitation of Peter the Great of Prussia, Euler went to Berlin as the director of the Institute of Physics and Mathematics of the Chinese Academy of Sciences until 1766, and later returned to Petersburg at the sincere invitation of Tsar Cadling II. Unexpectedly, not long after, his left eye vision decreased and he was completely blind. Unfortunate things followed. 177 1 year, the Petersburg fire damaged Euler's residence. 64-year-old Euler was blinded by illness and was trapped in the fire. Although he was saved from the fire by others, his research and a lot of research results were reduced to ashes.

The heavy blow still didn't make Euler fall, and he vowed to get the loss back. Before he was completely blind, he could still see vaguely. He seized the last moment, scribbled the formula he found on a big blackboard, and then dictated its contents, which were recorded by his students, especially his eldest son A Euler (mathematician and physicist). After Euler was completely blind, he still fought against the darkness with amazing perseverance and studied with memory and mental arithmetic until his death, which lasted 17 years.

Euler's memory and mental arithmetic are rare. He can retell the contents of his notes when he was young. Mental arithmetic is not limited to simple operations, and advanced mathematics can also be done by heart. An example is enough to illustrate his skill. Two students of Euler added the term 17 of a complex convergence series to the 50th place, and the difference between them was one unit. In order to determine who is right, Euler calculated all the operations carefully and finally found out the mistakes. Euler blindness 17 years; It also solved Newton's headache of moon deviation and many complicated analysis problems.

Euler has a high style. Lagrange is a great mathematician after Euler. From the age of 19, he communicated with Euler to discuss the general solution of isoperimetric problems, from which the variational method was born. The isoperimetric problem has been carefully considered by Euler for many years. Lagrange's solution won warm praise from Euler. 1759,10 On June 2, Euler praised Lagrange's achievements in his reply, and modestly temporarily suppressed his immature works in this respect, which enabled the young Lagrange's works to be published and circulated and won great reputation. In his later years, all mathematicians in Europe regarded him as a teacher. The famous mathematician Laplace once said, "Euler is our mentor." Euler's energy was maintained until the last moment. 1783 One afternoon in September, Euler invited his friends to dinner to celebrate his successful calculation of the law of balloon rising. At that time, Uranus had just been discovered, and Euler wrote the essentials of Uranus orbit calculation. He also laughs with his grandson. After drinking tea, he suddenly fell ill, and his pipe fell out of his hand, muttering, "I'm dead."

Euler's life is a life of struggle for the development of mathematics. His outstanding wisdom, tenacious perseverance, tireless spirit of struggle and noble scientific ethics are always worth learning. Euler also created many mathematical symbols, such as π( 1736), i( 1777), e( 1748), sin and cos( 1748), tg( 1753).

4. The Cartesian coordinate system we use now is usually called Cartesian coordinate system. Cartesian coordinate system was introduced from Descartes R. (1596.3.31~1650.2.11), and then people can study geometric problems by algebraic methods, establish and improve analytic geometry and establish calculus.

The French mathematician Lagrange (1736.1.25 ~1813.4.10) once said: "As long as algebra and geometry part ways, their progress will be slow and their application will be narrow. However, when these two kinds of science are combined into partners, they absorb fresh vitality from each other. Since then, it has been making rapid progress. "

China mathematician Hua (1910.1.12 ~1985.6.12) once said: "Numbers and shapes are interdependent. Without numbers, it is not so intuitive, and without numbers, it is difficult to be nuanced. The combination of form and number is good in all aspects, but everything is wrong without it. Don't forget, the unity of geometry and algebra is always connected and never separated! "

The words of these great men are actually comments on Descartes' contribution.

Cartesian coordinate system is different from general theorems and general mathematical theories. It is a kind of thinking method and skill, which has completely changed the whole mathematics and made Descartes one of the founders of modern mathematics.

Descartes was an outstanding French philosopher in the17th century, the founder of modern biology, and a first-rate physicist at that time, not a professional mathematician.

Descartes' father is a lawyer. When he was eight years old, his father sent him to a missionary school. He left school at the age of sixteen, then went to study at the University of Poitiers, and went to Paris as a lawyer after graduation at the age of twenty. 16 17 joined the army. During his nine years in the army, he has been studying mathematics in his spare time. Later, he returned to Paris and was excited about the power of the telescope. He studied the theory and structure of optical instruments behind closed doors, and at the same time studied philosophical problems. 1682 moved to the Netherlands and got a relatively quiet and free academic environment. He lived there for 20 years and completed many important works, such as Guiding Principles of Thought, World System, Methodology for Better Guiding Reasoning and Seeking Scientific Truth (including three famous appendices: Geometry, Refraction and Meteor) and so on. Among them, Appendix Geometry is the only mathematical book written by Descartes, which clearly reflects his thoughts on coordinate geometry and algebra. Descartes was invited to Sweden as the queen's teacher in 1649. The severe winter in Stockholm had a very bad influence on Descartes' weak body. Descartes suffered from pneumonia in February 1650 and died ten days later. He died in February 1650, 1 1, one month and three weeks before he was 54 years old.

Descartes liked mathematics since he was a child, but it was an accidental opportunity to really believe that he had a talent for mathematics and began to study it seriously.

Yes161811. Descartes served in the army and was stationed in a small city in the Netherlands to fill Boleda. One day, when he was walking in the street, he saw a group of people gathered near a sign posting a notice. They were talking excitedly. He approached curiously. But because he couldn't understand Dutch and the Dutch characters on the notice, he asked the people next to him in French. A passer-by who can understand French looked disapprovingly at the young soldier and told him that there was a prize contest to solve mathematical problems. If you want him to translate all the contents of the notice, you need one condition, that is, the soldiers should send him the answers to all the questions in the notice. The Dutch claimed that he was a teacher of physics, medicine and mathematics. Unexpectedly, the next day, Descartes really came to him with the answers to all the questions; What surprised Beckman in particular was that all the answers of the young French soldier were not wrong at all. As a result, the two became good friends, and Descartes became a frequent visitor to Beckman's house.

Descartes began to study mathematics seriously under the guidance of Beckman, who also taught Descartes to learn Dutch. This situation lasted for more than two years, which laid a good foundation for Descartes to create analytic geometry later. Moreover, it is said that the Dutch words that Buick taught Descartes also saved Descartes' life:

Descartes once sailed to France with his servant on a small merchant ship, and the fare was not very expensive. I didn't realize this was a pirate ship. The captain and his deputy thought that Descartes' master and servant were French and didn't understand Dutch, so they negotiated to kill them in Dutch and robbed them of their money. Descartes understood the words of the captain and his deputy, made preparations quietly, finally subdued the captain and returned to France safely.

After living in France for several years, in order to express his views on things in words, he left France with religious prejudice and secular autocracy and returned to the lovely and hospitable Netherlands. Even the conflict with pirates can't erase his fond memories of Holland. Descartes completed his geometry in Holland. This book is not long, but it is a treasure in geometry works.

Descartes died in Stockholm 16 years later, his ashes were sent back to Paris. Originally placed in Barville Abbey, 1667 moved to the French cemetery of great men-the sacred cemetery of Parisian defenders and celebrities. Many outstanding French scholars found their final destination there.

5. Gauss (C.F. Gauss,1777.4.30 ~1855.2.23) is a German mathematician, physicist and astronomer, who was born in a poor family in Zwick, Germany. His father, Gerhard Di Drich, worked as a berm, bricklayer and gardener. His first wife lived with him for more than 65,438+00 years and died of illness, leaving him no children. Diderich later married Luo Jieya, and the next year their child Gauss was born, which was their only child. My father is extremely strict with Gauss, even a little too strict. He often likes to plan his life for the young Gauss according to his own experience. Gauss respected his father and inherited his honest and cautious character. De Derrick died in 1806, when Gauss had made many epoch-making achievements.

In the process of growing up, young Gauss mainly paid attention to his mother and uncle. Gauss's grandfather was a stonemason who died of tuberculosis at the age of 30, leaving two children: Gauss's mother Luo Jieya and his uncle Flier. Flier Ritchie is smart, enthusiastic, intelligent and capable, and devoted himself to the textile trade with remarkable achievements. He found his sister's son clever, so he spent part of his energy on this little genius and developed Gauss's intelligence in a lively way. A few years later, Gauss, who was an adult and achieved great success, recalled what his uncle had done for him and felt that it was crucial to his success. He remembered his prolific thoughts and said sadly, "We lost a genius because of the death of our uncle". It is precisely because Flier Ritchie has an eye for talents and often persuades her brother-in-law to let her children develop into scholars that Gauss didn't become a gardener or a mason.

In the history of mathematics, few people are as lucky as Gauss to have a mother who strongly supports his success. Luo Jieya got married at the age of 34 and was 35 when she gave birth to Gauss. He has a strong personality, wisdom and sense of humor. Since his birth, Gauss has been very curious about all phenomena and things, and he is determined to get to the bottom of it, which is beyond the scope allowed by a child. When the husband reprimands the child for this, he always supports Gauss and resolutely opposes the stubborn husband who wants his son to be as ignorant as he is.

Luo Jieya sincerely hopes that his son can do something great and cherish Gauss's talent. However, he was afraid to put his son into mathematics research that could not support his family at that time. /kloc-when she was 0/9 years old, although Gauss had made many great achievements in mathematics, she still asked her friend W. Bolyai (the father of J. Bolyai, one of the founders of non-Euclidean geometry): Will Gauss have a future? W Bolyai said that her son would become "the greatest mathematician in Europe", and her eyes were filled with tears.

At the age of seven, Gauss went to school for the first time. Nothing special happened in the first two years. 1787 years old, Gauss 10. He entered the first math class. Children have never heard of such a course as arithmetic before. The math teacher is Buttner, who also played a certain role in the growth of Gauss.

A story that is widely circulated all over the world says that when Gauss was at 10, by adding all the integers from 1 to 100, he worked out the arithmetic problem that Butner gave to the students. As soon as Butner described the question, Gauss got the correct answer. However, this is probably an untrue legend. According to the research of E·T· Bell, a famous mathematical historian who has studied Gauss, Butner gave the children a more difficult addition problem: 81297+81495+81693+…+100899.

Of course, this is also a summation problem of arithmetic progression (the tolerance is 198 and the number of items is 100). As soon as Butner finished writing, Gauss finished the calculation and handed in the small tablet with the answers written on it. E. T. Bell wrote that in his later years, Gauss often liked to talk about this matter with people, saying that only his answer was correct at that time, and all the other children were wrong. Gauss didn't specify how he solved the problem so quickly. Mathematical historians tend to think that Gauss had mastered arithmetic progression's summation method at that time. For a child as young as 10, it is unusual to discover this mathematical method independently. The historical facts described by Bell according to Gauss's own account in his later years should be more credible. Moreover, it can better reflect the characteristics that Gauss paid attention to mastering more essential mathematical methods since he was a child.

Gauss's computing ability, mainly his unique mathematical methods and extraordinary creativity, made Butner sit up and take notice of him. He specially bought Gauss the best arithmetic book from Hamburg and said, "You have surpassed me, and I have nothing to teach you." Then Gauss and Bater's assistant Bater established a sincere friendship until Bater died. They studied together and helped each other, and Gauss began real mathematics research.

1788, 1 1 year-old gauss entered a liberal arts school. In his new school, all his classes are excellent, especially classical literature and mathematics. On the recommendation of Bater and others, the Duke of zwick summoned Gauss, who was 14 years old. This simple, clever but poor child won the sympathy of the Duke, who generously offered to be Gauss' patron and let him continue his studies.

Duke Brunswick played an important role in Gauss's success. Moreover, this function actually reflects a model of scientific development in modern Europe, indicating that private funding was one of the important driving factors for scientific development before the socialization of scientific research. Gauss is in the transition period of privately funded scientific research and socialization of scientific research.

1792, Gauss entered Caroline College in Brunswick for further study. 1795, the duke paid various expenses for him and sent him to the famous University of G? ttingen in Germany, which made Gauss study hard and started creative research according to his own ideals. 1799, Gauss finished his doctoral thesis and returned to his hometown of Brunswick-Zwick. Just when he fell ill because he was worried about his future and livelihood-although his doctoral thesis was successfully passed, he was awarded a doctorate and obtained a lecturer position, but he failed to attract students, so he had to go back to his hometown and the duke gave him a helping hand. The Duke paid for the printing of Gauss's long doctoral thesis, gave him an apartment, and printed Arithmetic Research for him, so that the book could be published in 180 1. Also bear all the living expenses of Gauss. All this moved Gauss very much. In his doctoral thesis and arithmetic research, he wrote a sincere dedication: "To Dagong" and "Your kindness relieved me of all troubles and enabled me to engage in this unique research".

1806, the duke was killed while resisting the French army commanded by Napoleon, which dealt a heavy blow to Gauss. He is heartbroken and has long been deeply hostile to the French. The death of Dagong brought economic difficulties to Gauss, the misfortune that Germany was enslaved by the French army, and the death of his first wife, all of which made Gauss somewhat disheartened, but he was a strong man and never revealed his predicament to others, nor did he let his friends comfort his misfortune. It was not until19th century that people knew his state of mind at that time when sorting out his unpublished mathematical manuscripts. In a discussion of elliptic functions, a subtle pencil word was suddenly inserted: "For me, it is better to die than to live like this."

The generous and kind benefactor died, and Gauss had to find a suitable job to support his family. Because of Gauss's outstanding work in astronomy and mathematics, his fame spread all over Europe from 1802. The Academy of Sciences in Petersburg has continuously hinted that since Euler's death in 1783, Euler's position in the Academy of Sciences in Petersburg has been waiting for a genius like Gauss. When the Duke was alive, he strongly discouraged Gauss from going to Russia. He is even willing to raise his salary and set up an observatory for him. Now, Gauss is facing a new choice in life.

In order not to lose Germany's greatest genius, B.A. von von humboldt, a famous German scholar, joined other scholars and politicians to win Gauss the privileged positions of professor of mathematics and astronomy at the University of G? ttingen and director of the G? ttingen Observatory. 1807, Gauss went to Kottingen to take office, and his family moved here. Since then, he has lived in G? ttingen except for attending a scientific conference in Berlin. The efforts of Humboldt and others not only made the Gauss family have a comfortable living environment, but also enabled Gauss himself to give full play to his genius, and created conditions for the establishment of Gottingen Mathematics School and Germany to become a world science center and mathematics center. At the same time, it also marks a good beginning of scientific research socialization.

Gauss's academic position has always been highly respected by people. He has the reputation of "prince of mathematics" and "king of mathematicians" and is considered as "one of the three (or four) greatest mathematicians in human history" (Archimedes, Newton, Gauss or Euler). People also praised Gauss as "the pride of mankind". Genius, precocity, high yield, persistent creativity, ..., almost all the praises in the field of human intelligence are not too much for Gauss.

Gauss's research field covers all fields of pure mathematics and applied mathematics, and has opened up many new fields of mathematics, from the most abstract algebraic number theory to intrinsic geometry, leaving his footprints. Judging from the research style, methods and even concrete achievements, he is the backbone of 18- 19 century. If we imagine mathematicians in the18th century as a series of high mountains, the last awe-inspiring peak is Gauss; If mathematicians in the19th century are imagined as rivers, then their source is Gauss.

Although mathematical research and scientific work did not become an enviable career at the end of 18, Gauss was born at the right time, because the development of European capitalism made governments around the world pay attention to scientific research when he was almost 30 years old. With Napoleon's emphasis on French scientists and scientific research, Russian czars and many European monarchs began to look at scientists and scientific research with new eyes. The socialization process of scientific research is accelerating and the status of science is improving. As the greatest scientist at that time, Gauss won many honors, and many world-famous scientists regarded Gauss as their teacher.

1802, Gauss was elected as an academician of communication and a professor of Kazan University by the Academy of Sciences in Petersburg, Russia. 1877, the Danish government appointed him as a scientific adviser, and this year, the government of Hanover, Germany also hired him as a government scientific adviser.

Gauss's life is a typical scholar's life. He has always maintained the frugality of a farmer, making it hard to imagine that he is a great professor and the greatest mathematician in the world. He was married twice, and several children annoyed him. However, these have little influence on his scientific creation. After gaining a high reputation and German mathematics began to dominate the world, a generation of Tianjiao completed the journey of life.

6. Pythagoras (Pythagoras, 572 BC? ~ 497 BC? ), an ancient Greek mathematician and philosopher.

Pythagoras and his school have many creations in mathematics, especially interested in the changing law of integers. For example, a number whose sum of all factors (except itself) is equal to itself is called a perfect number (such as 6,28,496, etc.). ), and the number greater than its factor is called abundance; The number less than the sum of its factors is called deficit. They also found that "the sum of the squares of two right angles of a right triangle is equal to the square of the hypotenuse", which is called Pythagorean Theorem in the West and Pythagorean Theorem in China.

In geometry, the Pythagorean school proved that the sum of the interior angles of a triangle is equal to two right angles. Studied the golden section; The method of regular pentagon and similar polygon was found. It is also proved that there are only five regular polyhedrons-regular tetrahedron, regular hexahedron, regular octahedron, regular dodecahedron and regular icosahedron.

7. Qian Xuesen 19 1 1 was born in Shanghai, and 1934 graduated from Shanghai Jiaotong University. In order to serve the motherland better, he was admitted to MIT for further study on 1935, and transferred to California Institute of Technology for further study on 1936, where he studied aviation engineering theory under the famous aviation scientist von Carmen. Qian Xuesen studied hard, got his doctorate three years later, and stayed in school to teach. Under the guidance of von Carmen, Qian Xuesen became interested in rocket technology and made great progress in the research fields of high-speed aerodynamics and jet propulsion. Soon, under the recommendation of Von Carmen, Qian Xuesen became the youngest tenured professor of California Institute of Technology.

From 1935 to 1950, Qian Xuesen made great academic achievements and paid well all his life, but he always missed his motherland.

1950 When the Korean War broke out, Qian Xuesen's desire to return to China to serve the motherland failed, and Qian Xuesen was persecuted because he came from China. Until June 1955, Qian Xuesen wrote to Comrade Chen Shutong, then vice chairman of the National People's Congress Standing Committee (NPCSC), asking the party and government to help him return to the embrace of the motherland at an early date. Premier Zhou attached great importance to this matter and instructed relevant personnel to deal with it at an appropriate time. After hard work, in June 195565438+ 10/8, Qian Xuesen's family finally returned to the motherland after 20 years' absence. Soon, he was appointed as the director of the Institute of Mechanics, Chinese Academy of Sciences.

In order to improve China's national defense capability and safeguard national security, China's first missile research institution, the Fifth Research Institute of the Ministry of National Defense, was established on 19561October 8, with Qian Xuesen as the first president. Under the guidance of Qian Xuesen, through hard work, China's first domestic missile was finally manufactured successfully in 1960+00.

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