Algebraic expression knowledge about division (1) multiplied by monomial or monomial.
(2) Multiply the monomial with the polynomial to get a polynomial with the same number of terms as the polynomial in the factor.
(3) Pay attention to the symbol problem when calculating. Each term of a polynomial contains the symbol before it, and we should also pay attention to the symbol of a single term.
(4) In the expansion of polynomial multiplication, if there are similar items, they should be merged.
(5) The letters in the formula can represent numbers, monomials or polynomials.
General steps of factorization (1) If every term of a polynomial has a common factor, then the common factor is extracted first.
(2) After the common factor is put forward or not, observe the number of terms in the polynomial: two terms can be decomposed by formula; We can try to find these three terms by formula method and cross multiplication decomposition factor; For four or more items, you can try the group decomposition method to decompose the factors.
(3) The factory must be decomposed until every element can no longer be decomposed.
Solution set of knowledge point inequality in junior high school mathematics inequality
For an inequality with an unknown number, any value of the unknown number suitable for this inequality is called the solution of this inequality.
For an unknown inequality, the set of all its solutions is called the solution set of this inequality.
The process of finding the solution set of inequality is called solving inequality.
Basic properties of inequality
Add (or subtract) the same number or the same algebraic expression on both sides of (1) inequality, and the direction of inequality remains unchanged.
2. Both sides of the inequality are multiplied by (or divided by) the same positive number, and the direction of the inequality remains unchanged.
(3) When both sides of the inequality are multiplied by (or divided by) the same negative number, the direction of the inequality changes.
Solution of quadratic equation in one variable ①. Direct Kaiping method
Using the definition of square root to find the solution of quadratic equation in one variable is called direct Kaiping method. The direct Kaiping method is suitable for solving quadratic equations with one variable. According to the definition of square root, it is the square root of b, when B < 0, the equation has no real root.
(2) Matching method
Matching method is an important mathematical method, which is not only suitable for solving quadratic equations with one variable, but also widely used in other fields of mathematics. The theoretical basis of the matching method is the complete square formula. If a in the formula is regarded as an unknown x and replaced by x, there is.
③ Formula method
Formula method is a method to solve the quadratic equation of one variable by finding the root formula, and it is a general method to solve the quadratic equation of one variable.
The formula for finding the root of quadratic equation with one variable;
④ factorization method
Factorization is to find the solution of the equation by factorization. This method is simple and easy to use, and it is the most commonly used method to solve the quadratic equation of one variable.
The above are the math knowledge points from Grade One to Grade Three that I summarized for you, for reference only, and I hope it will help you.