Enclose several numbers in braces and separate two adjacent numbers with commas, such as {1, 2}, {1, 4,7}, ... We call it a set, and each number is called an element of the set. If all elements of a set are rational numbers, then when the rational number x is an element of the set,
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Mathematics is a universal means for human beings to strictly describe and deduce the abstract structure and mode of things, and can be applied to any problem in the real world. All mathematical objects are artificially defined in essence. In this sense, mathematics belongs to formal science, not natural science. Different mathematicians and philosophers have a series of views on the exact scope and definition of mathematics.
Mathematics plays an irreplaceable role in the development of human history and social life, and it is also an indispensable basic tool for studying and studying modern science and technology.
Its plural form in English and plural form in French plus -es constitute mathématiques, which can be traced back to the neutral plural mathematica in Latin. Cicero translated it from the Greek plural τ α α θ ι α κ? (ta mathē matiká). In ancient China, mathematics was called arithmetic, also called arithmetic, and finally it was changed to mathematics. Arithmetic in ancient China was one of the six arts.
Mathematics originated from the early production activities of human beings, and the ancient Babylonians had accumulated some mathematical knowledge, which could be applied to practical problems. As far as mathematics itself is concerned, their mathematical knowledge is only obtained through observation and experience, and there is no comprehensive conclusion and proof, but their contribution to mathematics should also be fully affirmed.
The knowledge and application of basic mathematics is an indispensable part of individual and group life. The refinement of its basic concepts can be found in ancient mathematical documents of ancient Egypt, Mesopotamia and ancient India. Since then, its development has continued to make small progress. But algebra and geometry at that time were still in an independent state for a long time.