First, the algebraic expression Dà Dà I Shü shü (algebraic expression) the basic explanation of mathematical terms. See "Mathematical Nouns". [Edit this paragraph] 2. Algebraic expressions of mathematical nouns: expressions obtained by finite algebraic operations such as addition, subtraction, multiplication, division, multiplication and square root between numbers and letters representing numbers, or mathematical expressions containing letters are called algebraic expressions. For example: ax+2b, -2/3, b 2/26, √a+√2, etc. Note: 1, excluding equal sign (=, ≦), unequal sign (≦, ≤, ≥,,,) and approximate equal sign ≈. 2. There can be absolute values. For example: |x|, |-2.25| and so on. [Edit this paragraph] III. Classification of algebraic expressions Algebraic expressions | Rational expressions ||||||| Algebraic expressions ||||||| Polynomial expressions||||| Monomial expressions||||| Fractions| Unreasonable expressions [Edit this paragraph] IV. Requirements of educational syllabus for algebraic expressions 1. Understand the concept of algebraic expressions and enumerate simple algebraic expressions. If we understand the concept of algebraic value, we can get the algebraic value correctly. 2. Understanding the concepts of algebra, monomial and polynomial will arrange polynomials in descending order (or ascending order), and understanding the concepts of similar items will merge similar items; 3. Master same base powers's multiplication, division, power multiplication algorithm and product multiplication algorithm, and be proficient in the operation of digital exponential power; 4. Be able to skillfully use multiplication formulas (square difference formula, complete square formula and (x+a)(x+b)=x2+(a+b)x+ab) for operation; 5. Master the operations of addition, subtraction, multiplication, division and power of algebraic expressions, and can perform simple mixed operations of addition, subtraction, multiplication, division and power of algebraic expressions. Focus 1. Related concepts of algebraic expressions. (1) Algebraic expression: Algebraic expression is a formula formed by connecting numbers or letters representing numbers with operation symbols (addition, subtraction, multiplication, division, power and root). A single number or letter is also an algebraic expression. It's marked "