I. Addition, subtraction, multiplication and division of numbers
Addition and subtraction in 1 and 10
The addition and subtraction within 10 is the most basic knowledge point in junior high school mathematics, which requires students to master the addition and subtraction of various numbers and be able to use them flexibly.
Addition and subtraction within 2.20
Based on the addition and subtraction within 10, this paper introduces the calculation methods of carry and borrow, and requires students to master all kinds of principles and methods of carry and borrow.
3. Multiplication formula
Multiplication formula is the content that junior high school mathematics must master. It can help students do multiplication quickly and improve their mathematical operation ability.
4. A preliminary understanding of division
The preliminary understanding of division is one of the key points in senior two mathematics learning, which requires students to understand the significance and basic properties of division and to perform simple division calculation.
Second, time addition, subtraction, multiplication and division
1 24-hour clock
The 24-hour system is the basis of the time system, which requires students to master the expression method of the 24-hour system and the conversion of time units.
2. Add, subtract, multiply and divide hours, minutes and seconds
The addition, subtraction, multiplication and division of hours, minutes and seconds is one of the most basic calculation methods in the time system, which requires students to master the calculation methods of addition, subtraction, multiplication and division of each time unit skillfully.
Third, the length of addition, subtraction, multiplication and division
1, length unit conversion
The conversion of length units is one of the most important knowledge points in junior high school mathematics, which requires students to master the conversion methods and usage scenarios between different length units.
2. Addition, subtraction, multiplication and division of meters, decimeters and centimeters
Meter, decimeter and centimeter are the most basic units in length measurement, so students need to master the calculation methods of addition, subtraction, multiplication and division of each unit skillfully.
Fourth, other formulas
1, area formula
Rectangular area = length× width;
Square area = side length × side length;
Circular area =πx radius? ;
The above are some basic area formulas, and students need to master their calculation methods and usage scenarios.
2. Volume formula
Cuboid volume = length× width× height;
Cubic volume = side length × side length × side length;
Cylinder volume =πx radius? X height;
Cone volume =πx radius? X height/3;
These are basic volume formulas, and students need to master their calculation methods and usage scenarios.
3, surface area formula:
Cuboid surface area =2x length x width +2x length x height +2x width x height;
Cubic surface area =6x side length? ;
Cylinder surface area =2xπx radius x height +2xπx radius? ;
These are basic surface area formulas, and students need to master their calculation methods and usage scenarios.
4. Volume formula: cuboid volume = length× width× height;
Cubic volume = side length x side length x side length;
Cylinder volume =πx radius? X height;
These are basic volume formulas, and students need to master their calculation methods and usage scenarios.
Generally speaking, the knowledge points of mathematics in the first, second and third grades are very basic and important, and students need to study and master them seriously. I hope that the introduction of this paper can help students better understand and remember these mathematical formulas, and lay a solid foundation for future mathematical learning and practical application.