Introduction to mathematics

Mathematics [English: Mathematics, from ancient Greece μ? θξμα(máthēma)； Often abbreviated as math or maths], it is a discipline that studies concepts such as quantity, structure, change, space and information.

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.

amount

Due to the need of counting, human beings abstract natural numbers from physical objects, which is the starting point of all "numbers" in mathematics. Natural number does not close subtraction. For closed subtraction, we extend the number system to integers. In order not to close division, but to close division, we extend the number system to rational numbers; For open root operation, we extend the number system to algebraic number (in fact, algebraic number is a broader concept).

On the other hand, for the limit operation is not closed, we extend the number system to real numbers. Finally, in order to prevent negative numbers from operating to even powers in the real number range, we extend the number system to complex numbers. A complex number is the smallest algebraic closed field containing real numbers. We perform four operations on any complex number, and the simplification results are all complex numbers.