Negative numbers are introduced as follows:

Negative number, the full name of negative real number, is a mathematical term, like? 3、? 1.5、? 1/2、? 584 and so on. Add "?" Before a positive number. The number of symbols is called a negative number. 0 is neither positive nor negative. Negative numbers and positive numbers represent quantities with opposite meanings.

Use minus sign (minus sign) "?" A positive sign, like what? 2 stands for the antonym of 2. Therefore, any positive number preceded by a negative sign becomes a negative number. A negative number is the reciprocal of its absolute value. On the number axis, negative numbers are all on the left of 0, and the earliest record of negative numbers is China's ancient mathematical work "Nine Chapters Arithmetic".

In the calculation, it is stipulated that "positive calculation is red and negative calculation is black", that is, red calculation is used to represent positive numbers and black is used to represent negative numbers. Comparing the sizes of two negative numbers, the absolute value is larger but smaller.

The reciprocal is introduced as follows:

Reciprocal/multiplicative inverse is a mathematical term, and the pinyin is dào shù. Mathematically, it means that the product of a number x multiplied by it is 1, which is recorded as 1/x, and the process is "multiplication inverse". All numbers except 0 have reciprocal, and the numerator and denominator, in turn, are the reciprocal of 1, and 0 has no reciprocal.

Mathematics is introduced as follows:

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.