An equation containing an equal sign is called an equation. Equations can be divided into contradictory equations and conditional equations. Adding (or subtracting) the same algebraic expression on both sides of the equation, or multiplying or dividing the same algebraic expression that is not zero on both sides of the equation, or multiplying the left and right sides of the equation at the same time, the equation still holds.
This equation is transitive. The properties of equations are the basis of solving equations, and many methods of solving equations should be applied to the properties of equations. If the term is shifted, the properties of the equation 1 are applied; Remove the denominator and apply Attribute 2 of the equation. By using the properties of the equation, when doing division, it should be noted that after conversion, the divisor cannot be 0, otherwise it is meaningless.
An identity is an equation. No matter how its variables are taken, it always holds. The range of identity is the common part of the definition range of left and right functions, but two independent functions have their own definition ranges, which are different from X identity in non-negative real number set and X identity in real number set.
Math:
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.