1, the essence of number axis and absolute value (especially the essential attribute of absolute value, including the absolute value of any two number differences);
2. Basic operations of power, monomial and polynomial;
3, specialized computing ability training
(1) Memory of common numbers-1 ~ 20 square, 1~ 10 cubic,1quadratic ~1quadratic;
(2) Multiplication formula (adding cubic difference and cubic sum formula on the basis of junior high school);
(3) radical type and polymorphism;
(4) Cross multiplication and matching method;
(5) factorization;
(6) The relationship between the roots and coefficients of a quadratic equation;
(7) Binary quadratic equation;
(8) Representation of the solution set of one-dimensional linear inequality on the number axis;
(9) Solving fractional equations and irrational equations;
4. The basic knowledge of quadratic function, the maximum value of quadratic function, the relationship between quadratic function image and each coefficient;
5. The positional relationship between straight lines and circles, and between circles;
This is a problem reflected by my years of teaching experience and students. I hope it will be helpful to your study. The poor foundation of junior high school is not terrible. I'm afraid you haven't attended junior high school at all, and you can't even add, subtract, multiply and divide the most basic rational numbers. Then you will have to start studying again from the first grade, but the key point is to learn what I listed above. Among them, computing ability is a very important ability, which has a great influence on your high school study; Among them, cross multiplication and matching methods must be very skilled. This is not difficult, just do the problem in a down-to-earth manner. If you have any questions, please ask. I have a whole set of exercises that I can send to you. If you have a mailbox.