Principle of difference invariance
The principle of difference invariance means that the minuend and the minuend decrease or increase the same number at the same time, and the difference is unchanged. The principle of difference invariance is often used to solve the problem of graphic area. If you can't think of this principle, it's hard to think of other ways to solve this problem. An obvious feature of this kind of problem is that.
Solve the area difference between two graphs, and there will be a common part in the graphs, which can be easily solved by using the principle of difference invariance. An obvious feature of this kind of topic. In mathematical terms, the difference is constant. Difference is constant: one minuend adds a few, and the other minuend adds the same number, and the difference is constant. The sum is constant: one addend adds a few, the other addend subtracts the same number, and the sum is constant.
Knowledge expansion:
Mathematics is a subject 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.
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.