The general steps of algebraic expression addition and subtraction: remove brackets; Merge similar projects. The evaluation of algebraic expression on addition, subtraction and simplification: simplify first: remove brackets and merge similar items; Post-evaluation: Substitute the numerical value into the calculation.

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Algebraic formula is the general name of monomial and polynomial, and it is a part of rational formula. In rational expressions, there can be five operations: addition, subtraction, multiplication, division and multiplication, but in algebraic expressions, the divisor cannot contain letters.

Definition:

Factorization: transforming a polynomial into the product of several simplest algebraic expressions is called factorization of this polynomial (also called factorization). Factorization and algebraic expression multiplication are opposite deformations.

Method:

There is no universally applicable rule for factorization. In junior high school mathematics textbooks, methods such as improving common factor method, formula method, grouping decomposition method, cross multiplication method, collocation method, undetermined coefficient method and term decomposition method are mainly introduced.

Take out the common factor: also known as the common factor extraction method. The factors contained in each term of a polynomial are called the common factors of the polynomial.

If every term of a polynomial has a common factor, it can be extracted as a factor of the polynomial, and the formula after extracting the common factor is put in brackets as another factor. This factorization method is called extraction of common factors. Simplification refers to the process of transforming complex formulas in physics, chemistry and mathematics into simple formulas.

Simplification is widely used in physics, chemistry and mathematics. Simplification is a very important concept in mathematics. A complex formula must be simplified to find its value simply.

Simplification can be divided into algebraic expression simplification, fractional simplification and solving equations. Simplification of algebraic expressions includes shifting terms, merging similar terms and removing brackets. Solving equations with fraction abbreviated as reduction can also be regarded as a simplified process. Simplified formulas are generally the simplest.

Algebraic simplification mainly includes algebraic addition, subtraction, multiplication, division and multiplication. Application of variance formula and complete square formula; Solving simple practical problems by the operation of algebraic expressions.

The general order of algebraic expression simplification: multiply first, then multiply and divide, and finally add and subtract. Using the first formula of the multiplication formula can make the calculation simple.

The simplified result needs to be simplified. If the final result contains similar items, similar items should be merged. When finding the value of algebraic expression, in order to make the calculation simple, it is generally necessary to simplify it first and then substitute it for evaluation.